SIG 553 Manuel SG553 En
User Manual: SIG 553
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SG 553
Assault Rifle
Caliber 5.56 mm (.223)
Manual
SG 553 Manual
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© 2011 SAN Swiss Arms AG, CH-8212 Neuhausen a. Rhf.
Technical edition by Michael R. Freiermuth, NetElite, CH-8048 Zürich
All rights reserved.
Published 2011
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40425014_SG553_EN_BA_9.8.1_INNENTEIL
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1 Safety warnings
Assault Rie SG 553
1.1 Handling
The safety warnings in this booklet are important. By understanding the
dangers inherent in the use of any rearm, and by taking the precautions
described herein, you can enjoy complete safety in the use of your Rie.
Failure to heed any of these warnings may result in serious injury to you
or others, as well as severe damage to the rearm or other property.
1.1.1 Dangerous Weapons
PISTOLS, REVOLVERS, SHOTGUNS and RIFLES are classied
as FIREARMS or DANGEROUS WEAPONS and are sold by us
with the specic understanding that we are not responsible in any
manner whatsoever for their safe handling or resale under local laws
and regulations. SAN Swiss Arms AG shall not be responsible in any
manner whatsoever for malfunctioning of the rearm, for physical injury
or for property damage resulting in whole or in part from (1) criminal or
negligent discharge, (2) improper or careless handling, (3) unauthorized
modications, (4) defective, improper, hand-loaded, or reloaded
ammunition, (5) corrosion, (6) neglect, or (7) other inuences beyond
our direct and immediate control.
This limitation applies regardless of whether liability is asserted on the
basis of contract, negligence or strict liability (including any failure to
warn). Under no circumstance shall SAN Swiss Arms AG be liable for
incidental or consequential damages, such as loss of use of property,
commercial loss and loss of earnings or prots.
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1.1.2 15 commandments of
rearms safety
1. ALWAYS carry the rie loaded
with the safety lever in the “S”
(SAFE) position.
2. Keep the safety lever on “S”
(SAFE) unless actually ring.
3. ALWAYS treat every gun as if
it were loaded.
4. ALWAYS be sure the barrel
is clear of any obstruction.
5. ALWAYS be sure of your
backstop, what lies beyond
and the safety of bystanders
before you shoot.
6. ALWAYS use clean, dry, ori-
ginal factory-made ammuni-
tion of the proper type and
caliber for your gun.
7. ALWAYS wear ear protection
and safety glasses when
shooting.
8. ALWAYS carry your gun so
that you can control the di-
rection of the muzzle if you
fall or stumble.
9. NEVER shoot at a at surface
or water.
10. DO NOT leave an unatten-
ded gun loaded. Guns and
ammunition should be stored
separately, locked if possib-
le, beyond the reach of child-
ren and careless adults.
11. NEVER allow your rearm
to be used by anyone who
has not read and understood
this instruction and safety
manual.
12. DO NOT point any gun,
loaded or unloaded, at any
undesired target.
13. NEVER re your rie near an
animal unless it is trained to
accept the noise: an animal’s
startled reaction could injure
it or cause an accident.
14. NEVER drink alcoholic be-
verages or take drugs before
or during shooting, as your
vision and judgment could be
seriously impaired making
your gun handling unsafe.
15. ALWAYS seek a doctor’s ad-
vice if you are taking medica-
tion, to be sure you are t to
shoot and handle your rie
safely.
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1.1.3 Protect your eyes and ears
Always wear adequate safety glasses and ear plugs or «earmuff» type
protectors whenever you are shooting. Always make certain that persons
close to you are similarly protected. Unprotected eyes may be injured by
powder gas, carbon residue, lubricant, metallic particles or similar de-
bris which may emanate occasionally from any rearm in normal use.
Without ear protection, repeated exposure to shooting noise may lead to
cumulative, permanent hearing loss.
1.1.4 Ammunition
1. Use only high quality, original factory-manufactured ammunition. Do
not use cartridges that are dirty, wet, corroded, bent, or damaged.
Do not oil cartridges. Do not spray aerosol-type lubricants,
preservatives, or cleaners directly onto cartridges or where excess
spray may ow into contact with cartridges. Lubricant or other foreign
matter on cartridges can cause potentially dangerous ammunition
malfunctions. Use only ammunition of the caliber for which your
rearm is chambered. The proper caliber is permanently engraved
on your rearm; never attempt to use ammunition of any other caliber.
2. The use of reloaded, «remanufactured», hand-loaded, or other non-
standard ammunition voids all warranties. Reloading is a science
and improperly loaded ammunition can be extremely dangerous.
Severe damage to the rearm and serious injury to the shooter or to
others may result.
Always use ammunition that complies with the industry performance
standards established by the Sporting Arms and Ammunition
Manufacturers’ Institute, Inc. of the United States (SAAMI).
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3. Firearms may be severely damaged and serious injury to the shooter
or to others may result from any condition causing excessive pressure
inside the chamber or barrel during ring. Excessive pressure can be
caused by obstructions in the barrel, propellant powder overloads, or
by the use of incorrect cartridges or defectively assembled cartridges.
In addition, the use of a dirty, corroded, or damaged cartridge can lead
to a burst cartridge case and consequent damage to the rearm and
personal injury from the sudden escape of high-pressure propellant
gas within the rearm’s mechanism.
4. Immediately stop shooting and check the barrel for a possible
obstruction whenever:
- you have difculty in, or feel unusual resistance in, cham bering a
cartridge, or;
- a cartridge misres (does not go off), or;
- the mechanism fails to extract a red cartridge case, or;
- unburned grains of propellant powder are discovered spilled in
the mechanism, or;
- a shot sounds weak or abnormal.
In such cases it is possible that a bullet is lodged part way down the
barrel. Firing a subsequent bullet into the obstructed barrel can wreck
the rearm and cause serious injury to the shooter or to bystanders.
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5. Bullets can become lodged in the barrel:
- if the cartridge has been improperly loaded without propellant
powder, or if the powder fails to ignite, (ignition of the cartridge
primer alone will push the bullet out of the cartridge case, but usu-
ally does not generate sufcient energy to expel the bullet com-
pletely from the barrel), or;
- if the bullet is not properly seated tightly in the cartridge case.
When such a cartridge is extracted from the chamber without be-
ing red, the bullet may be left behind in the bore at the point
where the riing begins. Subsequent chambering of another car-
tridge may push the rst bullet further into the bore.
6. If there is any reason to suspect that a bullet is obstructing the barrel,
immediately unload the rearm and look through the bore. It is not
sufcient to merely look in the chamber. A bullet may be lodged
some distance down the barrel where it cannot easily be seen.
IF A BULLET IS IN THE BORE, DO NOT ATTEMPT TO SHOOT IT
OUT BY USING ANOTHER CARTRIDGE, OR BY BLOWING IT OUT
WITH A BLANK OR ONE FROM WHICH THE BULLET HAS BEEN
REMOVED: SUCH TECHNIQUES CAN GENERATE EXCESSIVE
PRESSURE, WRECK THE FIREARM AND CAUSE SERIOUS
PERSONAL INJURY.
If the bullet can be removed with a cleaning rod, clean any unburned
powder grains from the bore, chamber, and mechanism before
resuming shooting. If the bullet cannot be dislodged by tapping it
with a cleaning rod, take the rearm to a gunsmith.
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7. Dirt, corrosion, or other foreign matter on a cartridge can impede
complete chambering and may cause the cartridge case to burst
upon ring. The same is true of cartridges which are damaged or
deformed.
8. Do not oil cartridges, and be sure to wipe the chamber clean of any
oil or preservative before starting to shoot. Oil interferes with the
friction between cartridge case and chamber wall that is necessary
for safe functioning, and subjects the rearm to stress similar to that
imposed by excessive pressure.
9. Use lubricants sparingly on the moving parts of your rearm. Avoid
excessive spraying of any aerosol gun care product, especially
where it may get on ammunition. All lubricants and aerosol spray
lubricants in particular can penetrate cartridge primers and cause
misres. Some highly penetrative lubricants can also migrate inside
cartridge cases and cause deterioration of the propellant powder; on
ring, the powder may not ignite. If only the primer ignites, there is
danger that the bullet may become lodged in the barrel.
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1.1.5 NEVER completely trust any safety
1. Your rearm comes equipped with an effective, well-designed safety
device:
HOWEVER, NEVER RELY COMPLETELY ON ANY SAFETY
MECHANISM.
It is NOT a substitute for cautious gun handling. NO safety,
however positive or well-designed, should be totally trusted.
Like all mechanical devices, the safety is subject to breakage or
malfunction and can be adversely affected by wear, abuse, dirt,
corrosion, incorrect assembly, improper adjustment or repair, or
lack of maintenance. Moreover, there is no such thing as a safety
which is «child-proof» or which can completely prevent accidental
discharge from improper usage, carelessness, or «horseplay».
The best safety mechanism is your own good sense; USE IT! Always
handle your rearm as though you expect the safety NOT to work!
2. While handling any rearm, do not allow it to point at any part of your
body or at another person. No harm will result if you obey this rule,
even if an accidental discharge occurs.
3. Never carry this rie with a cartridge in the chamber and the trigger
cocked.
4. Always keep your nger off the trigger and point the muzzle in a safe
direction when operating the gun.
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1.1.6 Loading
1. Always make sure the muzzle is pointed in a safe direction!
2. Never attempt to load or unload any rearm inside a vehicle, building
or other conned space (except a properly constructed shooting
range). Enclosed areas frequently offer no completely safe direction
to point the rearm; if an accidental discharge occurs, there is great
risk of injury or property damage.
3. Before loading, always clean all grease and oil from the bore and
chamber, and check to be certain that no obstruction is in the barrel.
Any foreign matter in the barrel could result in a bulged or burst barrel
or other damage to the rearm, and could cause serious injury to the
shooter or to others.
1.1.7 Firing
1. Keep the muzzle pointed in a safe direction and your nger away
from the trigger when cocking any rearm.
2. Never carry about or leave unattended any rearm which is cocked
and ready to re! When cocked, it will re from slight pressure on
the trigger. An accidental discharge could easily result if you fall or
drop the rearm, or if the rearm is struck or disturbed by someone
or something.
3. Never re any rearm with your nger, hand, face, or other part of
your body over or adjacent to the ejection port, or in any position
where you may be struck by reciprocating movement of the breech.
Both the ejection of empty cartridge cases and the movement of the
breech are part of the normal operating cycle of rearms, and pose
no safety hazard to the shooter if the rearm is held in a normal grip
and red at arm’s length.
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4. Never allow other persons to stand beside you where they might
be struck by an ejected cartridge case. The case is hot, and may
be ejected with sufcient force to cause a burn or cut or injure an
unprotected eye. Make certain there is a clear, unobstructed path for
safe ejection of the red case. Remember, the case may bounce off
a hard object nearby and strike you or someone else.
If, while shooting, your rearm develops a mechanical malfunction or
binding, or «spits» powder gas, or if a cartridge primer is punctured
or a cartridge case is bulged or ruptured, or if the report on ring does
not sound quite right, STOP SHOOTING IMMEDIATELY! It may be
dangerous to continue. UNLOAD THE FIREARM – do NOT try «one
more shot». Take the rearm and the ammunition to a gunsmith for
examination.
5. While shooting any rearm, an unred cartridge or red cartridge
case may occasionally become jammed between the slide and the
barrel.
Clear the jam as follows, WHILE KEEPING THE MUZZLE POINTED
IN A SAFE DIRECTION: Remove the magazine, then pull back the
slide and lock it to the rear by pushing up the slide release. The
jammed cartridge or case now can be removed by shaking it out or
by picking it out with the ngers.
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1.1.8 Unloading
1. Always make sure the muzzle is pointed in a safe direction!
2. Remember to clear the chamber after the magazine has been
removed.
3. Never assume that any gun is unloaded until you have personally
checked it!
4. After every shooting practice, make a nal check to be certain the
rearm is unloaded before leaving the range.
1.2 Transport and storage
When transporting your rearm to and from shooting activities, keep it
unloaded for your safety and for the safety of others.
When storing your rearm, keep it separated from ammunition, under
lock and key if possible, and out of the reach of children and other
inexperienced or unauthorized persons.
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1.3 Maintenance
All rearms require periodic maintenance and inspection which may re-
veal a need for adjustment or repair. Have your rearm checked by a
competent gunsmith annually even if it seems to be working well, since
breakage, improper functioning or corrosion of some components may
not be apparent from external examination.
If you notice any mechanical malfunction, do NOT continue to use the
rearm.
UNLOAD the rearm and take it to a competent gunsmith immediately
for a thorough examination. Similarly, if water, sand, or other foreign
matter enters the internal mechanism, immediately dismantle the re-
arm for a complete and thorough cleaning.
Failure to keep your rearm clean and inproper working order can lead
to a potentially dangerous condition and an accident causing serious
bodily injury or property damage may result.
1.4 Care and cleaning
1. Your rearm is delivered factory packaged and preserved with a
light coating of protective grease and oils. Before loading make
certain that all packing grease and oil has been cleaned from the
bore and exposed mechanism.
2. Before you begin to disassemble your rearm for cleaning, always
double-check to make sure it is unloaded!
3. After cleaning always check to be sure that no cleaning patch or
other obstruction remains in the bore or chamber!
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1.5 Parts
Our Service Department maintains a full complement of replacement
parts. Even though most gunsmiths have the knowledge, training and
ability to make the necessary repairs to your rearm, the skill and
workmanship of any particular gunsmith is totally beyond our control.
Should your rearm ever require service, we strongly recommend that
you return it to SAN Swiss Arms AG. Follow the instructions outlined
below. Remember, unauthorized adjustments of parts replacement can
void your warranty.
A rearm is a precision instrument and some replacement parts will re-
quire individual tting to ensure correct operation. A wrong part, improp-
er tting or incorrect mechanical adjustment may result in an unsafe
condition or dangerous malfunction, damage to the rearm, or possible
serious injury to the shooter or to others.
IF ANY PART IS ORDERED WITHOUT RETURNING THE FIREARM
TO SAN SWISS ARMS AG, the customer bears full responsibility for
ensuring that the part supplied is correct for his particular rearm and is
properly installed and tted by a qualied gunsmith.
SAN SWISS ARMS AG CANNOT BE RESPONSIBLE FOR THE FUNC-
TIONING OF ANY FIREARM IN WHICH REPLACEMENT PARTS ARE
INSTALLED BY OTHERS.
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1.6 SAN SWISS ARMS AG service policy
Before shipment your rearm was carefully inspected and test red in
order to ensure that it conformed to our specications and standards.
Should your rearm require adjustment, repair or renishing, we strongly
recommend that you return it to SAN Swiss Arms AG for factory service.
If there is any question regarding the performance of your rearm, please
write to SAN Swiss Arms AG Service Department, fully describing all cir-
cumstances and conditions involved. If our Service Department makes
the determination that your rearm requires factory service, you will be
so advised and will be given instructions for the most expeditious han-
dling of your shipment.
Our Service Department will give your rearm a complete inspection,
and evaluate the problem(s) specied in your letter.
lf the work required is not covered under the terms of our «Limited War-
ranty» (a copy is enclosed with your rearm), you will receive an actual
cost quotation, not an estimate. Any repair work must be authorized by
you, and no work will be done without your express approval.
To return any rearm to us for adjustment, repair or re nishing, please
follow these suggestions to expedite service:
1. Only federally licensed dealers may ship handguns via mail.
Handguns mailed by individuals are conscated by the Post Ofce.
2. Federal law permits you to return your rearm to the manufacturer for
service via common carriers or, if your rearm is a rie or shotgun, by
mail. However, state and local rearms laws vary greatly; you should
consult your local prosecuting attorney regarding any restrictive laws
in your jurisdiction regarding your shipment or receipt of rearms.
With the above in mind, it is strongly recommended that any rearm
sent to us for repair be sent through a federally licensed dealer.
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3. All rearms must be shipped to us prepaid.
WE WILL NOT ACCEPT COLLECT SHIPMENTS.
4. Firearms returned for repair should be addressed to:
SAN Swiss Arms AG
Industrieplatz
8212 Neuhausen am Rheinfall
Switzerland
5. Be sure to enclose a letter stating serial number, caliber and barrel
length of your rearm. Also state nature of trouble experienced or
work required. Merely stating «defective» or «repair as necessary»
is inadequate information. Be specic and enclose copies of any
previous correspondence.
6. FIREARMS MUST BE SHIPPED UNLOADED.
7. Double-check the chamber of your rearm before shipping. If
rearms are sent to SAN Swiss Arms AG in a loaded condition, we
are required by law to notify the Federal Authorities.
8. DO NOT include telescopic sights, custom stocks, slings, or other
accessories with any rearm shipped to us.
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2 Weapon theory
2.1 Weapon description
2.1.1 General
The SG 553 is a gas operated weapon with rotary bolt mechanism.
Figure 1: SG 553 SB Standard version with picatinny rail and ip up front and
rear sight and adjustable butt stock (optional)
Figure 2: SG 553 SB Standard version with diopter sight
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Figure 3: SG 553 LB Long barrel version with picatinny rail and ip up front and
rear sight and adjustable butt stock (optional)
Figure 4: SG 553 LB Long barrel version with diopter sight
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Field of application
SG 553 SB (short barrel)
• at distances of up to 300 m / 328 yds.
- in semi automatic re
- in rapid semi automatic re
- in three-round bursts
- in full auto operation
• at distances of up to 400 m / 437 yds., when tted with telescopic
sights
• the SG 553 can be red with the butt stock in the normal position or
folded back.
SG 553 LB (long barrel)
• at distances of up to 300 m / 328 yds.
- in semi automatic re
- in rapid semi automatic re
- in three-round bursts
- in full auto operation
• at distances of up to 400 m / 437 yds., when tted with telescopic
sights
• with the bayonet attached, as a cut and thrust weapon
(SG 553 LB only)
• as a grenade launcher (SG 553 LB only)
• the SG 553 can be red with the butt stock in the normal position or
folded back.
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2.1.2 Barrel with receiver and gas system
(SB, picatinny version)
The barrel is screwed into the receiver. The muzzle is tted with a
screwed on or integrated ash suppressor. The front sight mount, which
is xed to the barrel, contains the gas port, accepts the front sight and
gas system and also serves as a support for the handguard.
The receiver guides the bolt and houses the locking system. The rear
sight mount with diopter drum or integrated Picatinny rail with ip up rear
sight are also mounted on top of the receiver.
Figure 5: Barrel (SB), receiver with picatinny rail and ip up sight, gas system
(1) Flash suppressor
(2) Barrel SB
(3) Front sight
(4) Gas valve
(5) Gas piston
(6) Gas tube
(7) Picatinny rail
(8) Rear sight
(9) Front sight mount
(10) Receiver casing
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2.1.3 Barrel with receiver and gas system
(SB, diopter version)
Figure 6: Barrel (SB), receiver with diopter sight, gas system
(1) Flash suppressor
(2) Barrel SB
(3) Front sight
(4) Gas valve
(5) Gas piston
(6) Gas tube
(7) Rear sight
(8) Front sight mount
(9) Receiver casing
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2.1.4 Barrel with receiver and gas system
(LB, picatinny version)
Figure 7: Barrel (LB), receiver with picatinny rail and ip up sight, gas system
(1) Flash suppressor
(2) Barrel SB
(3) Front sight
(4) Gas valve
(5) Gas piston
(6) Gas tube
(7) Picatinny rail
(8) Rear sight
(9) Front sight mount
(10) Receiver casing
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2.1.5 Barrel with receiver and gas system
(LB, diopter version)
Figure 8: Barrel (LB), receiver with diopter sight, gas system
(1) Flash suppressor
(2) Barrel SB
(3) Front sight
(4) Gas valve
(5) Gas piston
(6) Gas tube
(7) Rear sight
(8) Front sight mount
(9) Receiver casing
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2.1.6 Bolt
The bolt consists of two main parts:
• Bolt head
• Bolt carrier
Bolt head
The bolt head locks the bolt assembly, houses the ring pin and the
extractor and feeds the cartridges to the chamber.
Figure 9: Bolt head
(1) Extractor
(2) Bolt head
(3) Firing pin
(4) Locking lug
(5) Control cam
(6) Firing pin stud
(7) Firing pin spring
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Bolt carrier
The bolt carrier guides the bolt head, controls the locking and unlocking
by means of the control cam, holds the gas piston and cocks the hammer.
Figure 10: Bolt carrier from left
(1) Bolt carrier
(2) Control cam
Figure 11: Bolt carrier from right
(1) Cocking lug
(2) Bolt carrier
(3) Charging handle catch
(4) Charging handle
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2.1.7 Handguard
The handguard protects the barrel and the gas system from damage and
provides protection from burning.
Figure 12: Handguard
Figure 13: 4-Rail-Handguard
(1) Handguard, upper part (2) Handguard, lower part
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2.1.8 Magazine
The magazine is transparent and has a capacity of 5, 10, 20 and 30
rounds.
On either side of the connectable casing there are connectors which
allow several magazines to be connected if required.
(1) Feeder
(2) Magazine spring
(3) Magazine oorplate
catch
(4) Magazine casing
(5) Magazine coupling lugs
(6) Magazine oorplate
Figure 14: Magazine 30 rounds, connectable
(1) Feeder
(2) Magazine spring
(3) Magazine oorplate
catch
(4) Magazine casing
(5) Magazine oorplate
Figure 15: Magazine 30 rounds, not
connectable
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2.1.9 Trigger assembly and butt stock
The trigger assembly comprises all the parts required for ring a shot.
The safety lever on both sides can be set to four positions:
Position «S» = The trigger is locked, the weapon is in safe position.
Position «1» = The weapon will re semi auto.
Position «3» = The weapon res 3-round burst.
After each burst, the trigger must be released and
then pulled again.
Position «20» = The weapon res in the full auto mode.
By pivoting the trigger guard to the right or left side the trigger becomes
accessible for shooting with mittens.
For safety reasons the trigger guard must not be shifted until just
before ring the weapon, and after ring it should be immediately
replaced in the normal position.
Figure 16: Trigger assembly and butt stock from right
(1) Butt stock
(2) Safety lever
(3) Trigger casing
(4) Pistol grip
(5) Trigger
(6) Magazine catch
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The ring mode is affected by the automatic ring lock (4):
• If the automatic ring lock is activated (white dot visible), shooting in
semi automatic re and rapid semi automatic re is possible.
• If the automatic ring lock is deactivated (white dot covered),
shooting in all ring modes is possible.
The positioning of the ring lock usually is predetermined by the rules of
engagement.
Figure 17: Trigger assembly and butt stock from left
(1) Trigger casing
(2) Bolt catch
(3) Safety lever
(4) Automatic ring lock
(5) Butt stock
(6) Magazine catch
(7) Trigger guard
(8) Pistol grip
(9) Butt stock catch
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2.2 Sights mechanism
The sights mechanism comprises either ip up sights or diopter sights.
2.2.1 Flip up sight mechanism
The ip up sight mechanism consists of the rear and front ip up sight.
The rear sight is marked with «100», corresponding to ring range
100 m / 109 yds.
The front sight is xed to its mount with the front sight screw. The folding
front sights are mounted on the lower part of the front sight.
(1) Rear sight holder
(2) Rear sight plate
(3) Flat head screw
Figure 18: Flip up rear sight
(1) Front sight
(2) Front sight holder
(3) Front sight screw
(4) Front sight disc
Figure 19: Flip up front sight
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2.2.2 Diopter sights mechanism
The diopter sights mechanism consists of the rear sight and front sight.
The diopter drum can be set to positions «1», «2» and «3», corresponding
to ring ranges 100 m (109 yds.), 200 m (218 yds.) and 300 m (328 yds.).
The positions marked in white correspond to aiming point = point of
impact.
Sighting position «1» is designed for immediate ring, and two luminous
dots are tted laterally for aiming at night.
(1) Receiver casing
(2) Rear sight mount
(3) Elevation correction
screw
(4) Rear sight drum
(5) Night sights
(6) Windage correction
screw
Figure 20: Diopter Sight
(1) Front sight tunnel
(2) Front sight
(3) Front sight screw
(4) Night front sight
Figure 21: Front sight with night front sight
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2.3 Technical specications
2.3.1 SG 553 SB Picatinny version
Caliber ...................................................mm ..............5.56
Total length ............................................mm ...............733
Length with butt stock folded .................mm ...............503
Barrel
Barrel length ..........................................mm ...............258
Number of grooves ..........................................................6
Riing
SG 553-1 ...............................................inches .............10
SG 553-2 ...............................................inches ...............7
Sights
Type ........................................................................ Flip up
Sight base ..............................................mm ...............340
Range adjustment..................................m ..................100
Trigger pull weight .................................N .....................35
Rate of re approx. ................................Rd./min ..700-850
Muzzle velocity V0 approx. .....................m/s ...............780
Muzzle energy E0 approx. .....................J .................1240
Weight
Weapon incl. empty magazine ...............g .................3200
Empty twenty-round magazine ..............g .....................95
Empty thirty-round magazine .................g ................... 110
Loaded twenty-round magazine ............g ...................340
Loaded thirty-round magazine ...............g ...................475
Subject to change without notice.
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2.3.2 SG 553 SB Diopter version
Caliber ...................................................mm ..............5.56
Total length ............................................mm ...............733
Length with butt stock folded .................mm ...............503
Barrel
Barrel length ..........................................mm ...............258
Number of grooves ..........................................................6
Riing
SG 553-1 ...............................................inches .............10
SG 553-2 ...............................................inches ...............7
Sights
Type ....................................................................... Diopter
Sight base ..............................................mm ...............340
Range adjustment..................................m ...........100-300
Trigger pull weight .................................N .....................35
Rate of re approx. ................................Rd./min ..700-850
Muzzle velocity V0 approx. .....................m/s ...............780
Muzzle energy E0 approx. .....................J .................1240
Weight
Weapon incl. empty magazine ...............g .................3180
Empty twenty-round magazine ..............g .....................95
Empty thirty-round magazine .................g ................... 110
Loaded twenty-round magazine ............g ...................340
Loaded thirty-round magazine ...............g ...................475
Subject to change without notice.
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2.3.3 SG 553 LB Picatinny version
Caliber ...................................................mm ..............5.56
Total length ............................................mm ...............822
Length with butt stock folded .................mm ...............592
Barrel
Barrel length ..........................................mm ...............347
Number of grooves ..........................................................6
Riing
SG 553-1 ...............................................inches .............10
SG 553-2 ...............................................inches ...............7
Sights
Type ........................................................................ Flip up
Sight base ..............................................mm ...............360
Range adjustment..................................m ..................100
Trigger pull weight .................................N .....................35
Rate of re approx. ................................Rd./min ..700-850
Muzzle velocity V0 approx. .....................m/s ...............850
Muzzle energy E0 approx. .....................J .................1480
Weight
Weapon incl. empty magazine ...............g .................3390
Empty twenty-round magazine ..............g .....................95
Empty thirty-round magazine .................g ................... 110
Loaded twenty-round magazine ............g ...................340
Loaded thirty-round magazine ...............g ...................475
Subject to change without notice.
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2.3.4 SG 553 LB Diopter version
Caliber ...................................................mm ..............5.56
Total length ............................................mm ...............822
Length with butt stock folded .................mm ...............592
Barrel
Barrel length ..........................................mm ...............347
Number of grooves ..........................................................6
Riing
SG 553-1 ...............................................inches .............10
SG 553-2 ...............................................inches ...............7
Sights
Type ....................................................................... Diopter
Sight base ..............................................mm ...............360
Range adjustment..................................m ...........100-300
Trigger pull weight .................................N .....................35
Rate of re approx. ................................Rd./min ..700-850
Muzzle velocity V0 approx. .....................m/s ...............850
Muzzle energy E0 approx. .....................J .................1480
Weight
Weapon incl. empty magazine ...............g .................3310
Empty twenty-round magazine ..............g .....................95
Empty thirty-round magazine .................g ................... 110
Loaded twenty-round magazine ............g ...................340
Loaded thirty-round magazine ...............g ...................475
Subject to change without notice.
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2.4 Accessories
Every SG 553 has the following accessories
• carrying sling
• loading tool
• cleaning kit
Figure 22: Carrying sling
Carrying sling in woven nylon with
two hooks, an adjustment clip and
a buckle
Figure 23: Loading tool NATO
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Figure 24: Cleaning kit NATO
(1) Weapon oil
(2) Cloth
(3) Weapon grease
(4) Case
(5) Cleaning brush
(6) Cleaning rod sections
(3 pcs.)
(7) Cleaning rod handle
(8) Cleaning cord for barrel
cleaning
(9) Cleaning jag
(10) Barrel brush
(11) Grease brush
(12) Chamber cleaning tool
(13) Gas tube brush
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3 Handling
3.1 Important instructions
1. The assault rie is to be considered as loaded until the user is con-
vinced of the contrary on the basis of his personal safety check.
2. If the rieman is holding the assault rie in his hand the barrel must
never be aimed at anything that he does not want to hit.
3. The trigger nger is to rest outstretched against the trigger casing
while the sights mechanism is not aiming at a target.
4. Every rieman is responsible for the use of his assault rie. He also
immediately discontinues ring against a command to the contrary
if he is convinced that he discerns a danger to humans and animals
or damage to material.
5. A barrel check must be performed prior to ring practice. Each shoo-
ter is responsible for the barrel check himself.
6. An unloading check is to be performed at the end of every ring
practice. Each shooter performs the unloading check himself.
7. The barrel must point in a safe direction while handling.
8. Only manipulation ammunition may be used for training in weapons
handling.
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9. Before entering the ring range:
a. The weapon is unloaded and the magazine kept separate from it;
b. The automatic ring lock is activated (white point visible);
c. The barrel check is performed;
d. The bolt is opened and locked in place with the bolt catch.
10. At the ring range:
a. The assault rie is to be left alone with bolt open, without magazine
and secured in the gun rack;
b. The assault rie may only be loaded in the shooting position;
the assault rie must be unloaded before leaving the shooting
position; the bolt remains open;
c. All handling in the shooting position is to be carried out with the
weapon in the ring position;
d. The unloading check is to be performed after shooting at the
range.
11. Upon leaving the ring range the automatic ring lock has to be set
relative to use (OPTIONAL).
12. Resting the assault rie on a human body while ring is prohibited.
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13. Hearing is to be protected with a hearing protector when shooting.
14. The assault rie may be loaded under cover, but the safety catch
may only be released in the shooting position. It can be reset upon
leaving the shooting position.
15. When ring while in motion the various ring positions are conside-
red to be the shooting position.
16. The contact position parallels the shooting position.
17. When repositioning the safety lever the trigger must not be pulled at
the same time.
18. Single, semi-auto burst or full-auto re while in motion may only be
shot when walking.
19. Single, semi-auto burst or full-auto re may be shot while in motion
as long as the assault rie is rested against the shoulder and is not
overshot or shot wide.
20. Shooting off more than six magazines in succession is prohi-
bited, no matter which type of re and ammunition is selec-
ted. The assault rie may only be reloaded when it has cooled
off sufciently so that the barrel can be gripped with bare hands.
Whenever possible submerge the weapon in water for cooling.
In cold weather or snow, however, it must not be dipped in the snow
or submerged in water.
If this instruction is not followed, autoignition or serious
damage due to the assault rie overheating can occur.
21. The weapon - bullet trap distance must be at least 50 m, provided
that the bullet trap is available in soft material visibly free of stones
(in permanent ring ranges particular rules apply with respect to the
composition of the bullet trap).
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22. If these conditions are met, there is no limit to the weapon - troop
distance when shooting at wood, cardboard, plastic and roller discs,
as well as discs with sackcloth covering.
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3.2 Loading the weapon
1. Set the safety lever to «S».
2. Swing the trigger guard into the vertical position.
3. Insert the magazine and check that it is properly seated by pres-
sing forward.
4. Carry out a loading cycle (pull the charging handle fully back and
let it run forward).
Figure 25: Inserting the magazine
(1) Safety lever
(2) Trigger guard
(3) Bolt
(4) Magazine
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3.3 Unloading (Clearing)
1. Set the safety lever to «S».
2. Swing trigger guard into vertical position.
3. Remove magazine by pressing magazine catch.
4. Pull the bolt to the rear, and lock it with the bolt catch.
Check the chamber, ensure that it is empty.
5. Point the weapon in a safe direction.
Set the safety lever to «1». Pull the trigger.
6. Set the safety lever to «S».
(1) Chamber
Figure 26: Check the chamber
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3.4 Changing the magazine
1. Set the safety lever to «S».
2. Swing the trigger guard into the vertical position.
3. Remove the magazine.
4. Insert a loaded magazine and ensure that it is properly seated by
pushing it forward.
3.5 Reloading
1. Set the safety lever to «S».
2. Swing the trigger guard into the vertical position.
3. Remove the empty magazine by pressing the magazine catch.
4. Insert a loaded magazine and check that it is properly seated by
pushing it forward.
5. Push the bolt catch up or pull back the charging handle slightly to
allow the bolt to run forward.
Figure 27: Push the bolt catch up
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3.6 Filling and coupling of magazines
3.6.1 Filling the magazine
1. Place the loading tool on the magazine.
2. Insert the ammunition clip and press the cartridges into the maga-
zine.
3. Remove the loading tool.
3.6.2 Coupling of magazines
1. Hold the magazine vertically.
2. With the oorplate of the second or third magazine pointing to the
rear, rst connect the upper lugs, then rotate it forward and connect
the lower lugs.
Coupling more than three magazines in sequence is not recom-
mended.
Figure 28: Filling the magazine Figure 29: Coupling of
magazines
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4 Aiming, ring, adjusting
4.1 Aiming, ring with ip up sight
To aim, align the eye, ip up rear sight, front sight and target.
At all ranges, the front sight should be aimed at the center of the target.
Firing or aiming is therefore «point of aim».
4.1.1 Adjusting
To correct the elevation, release the at head screw of the ip up sight
and shift the sight plate up- or downwards respectively, then lock the
at head screw.
Elevation
• High shots are corrected by shifting the sight plate down.
• Low shots are corrected by shifting the sight plate up.
(1) Rear sight holder
(2) Rear sight plate
(3) Flat head screw
Figure 30: Rear sight
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Windage
• Shots to the right are corrected by turning the front sight screw to
the right.
• Shots to the left are corrected by turning the front sight screw to the
left.
(1) Front sight
(2) Front sight holder
(3) Front sight screw
(4) Front sight disc
Figure 31: Front sight
4.1.2 Point of impact correction SG 553 with ip up sight
Firing range Average point of impact correction
Elevation: per one mark on the rear sight plate
Windage: per one turn of the front sight screw
SG 553 Windage Elevation
100 m / 109 yds.
200 m / 218 yds.
300 m / 328 yds.
23.5 cm / 9.3 inch
47.0 cm / 18.5 inch
70.5 cm / 27.8 inch
22 cm / 8.7 inch
44 cm / 17.3 inch
66 cm / 26.0 inch
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4.2 Aiming, ring with diopter sight
To aim, align the eye, diopter or battle sight, front sight and target. When
using the diopter, ensure that the periphery of the front sight tunnel and
the diopter aperture are concentric.
At all ranges, the front sight should be aimed at the center of the target.
Firing or aiming is therefore «point of aim».
Figure 32: Sight picture point of
aim
4.2.1 Adjusting with diopter sight
To correct for elevation and windage, the corresponding correction screw
is turned with a screwdriver.
By rotating the elevation correction screw and the windage correction
screw by one click, the average point of impact in the vertical respectively
the horizontal axis is displaced by approximately 0.15 ‰.
(1) Receiver casing
(2) Rear sight mount
(3) Elevation correction screw
(4) Rear sight drum
(5) Night sights
(6) Windage correction screw
Figure 34: Diopter Sight
Figure 33: Sight picture night sight
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Figure 35:
Correction symbol
on rear sight
(correction of
elevation)
Elevation:
Low shots are corrected
by turning the screw to
the right.
High shots are
corrected by turning
the elevation correction
screw to the left.
Figure 36:
Correction symbol
on rear sight
(correction of
windage)
Windage:
Shots to the left are
corrected by turning the
screw to the right.
Shots to the right are
corrected by turning
the windage correction
screw to the left.
4.2.2 Point of impact correction SG 553 with diopter sight
Firing range Average point of impact correction per
notch (diopter sight)
SG 553 Windage Elevation
100 m / 109 yds.
200 m / 218 yds.
300 m / 328 yds.
1.7 cm / 0.7 inch
3.4 cm / 1.3 inch
5.1 cm / 2.0 inch
2.4 cm / 0.9 inch
4.8 cm / 1.9 inch
7.2 cm / 2.8 inch
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4.3 Gas valve position
With the SG 553, the gas volume required for the function of the weapon
can be controlled by the gas valve.
4.3.1 Position I
(Rib of gas valve in vertical position)
Under normal conditions, ring is effec-
ted in this position.
4.3.2 Position II
(Rib of gas valve in slanting position)
When cycling or ejection problems oc-
cur due to heavy fouling or icing-up, the
gas valve is to be turned clockwise as
far as the stop. In this position, a larger
gas volume acts on the gas piston.
The adjustment of the gas valve is
effected manually, and, in case of a hot or heavily fouled weapon, by
means of a cartridge or auxiliary aid.
Firing with gas valve in position II is an exception. As soon as the weapon
works, the gas valve must be turned back to position I, otherwise the
recoil is intensied and the weapon is unnecessarily stressed.
Figure 37: Gas valve in position I
Figure 38: Gas valve in position II
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4.4 Foldable butt stock
Thumb in the butt stock catch and fold the butt stock so that it registers
with the handguard under spring pressure.
Figure 39: Butt stock folded
(1) Butt stock catch
(2) Butt stock
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4.5 Adjustable butt stock
The butt stock is adjustable in the length in 3 positions (position
completely extracted, center position, slide in position).
To adjust the butt stock, depress the adjusting latch (3), move the butt
stock (2) to the desired position, release the adjusting latch (3).
The butt stock can only be xed on the handguard in its extracted
position.
Figure 40: Butt stock adjustable, folded
(1) Butt catch
(2) Butt stock adjustable
(3) Adjusting latch
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4.6 Firing with mittens
For ring with mittens the trigger guard can be pivoted to the left or
right. For safety reasons the trigger guard must be placed in the vertical
position before carrying out any manipulations.
Figure 41: Trigger guard folded
(1) Trigger casing
(2) Trigger guard
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4.7 Rie Grenades (Bullet trap type)
4.7.1 General
Rie grenades can only be shot with the longbarrel (LB) version.
The rie grenades are intended to be launched in at trajectory.
Standard, live ammunition is used for launching, whereby the weapon
cycles automatically (The bullet is caught in the bullet trap integrated in
the grenade).
4.7.2 Handling
Acting on orders, or his own initiative in situations of danger, the trooper
prepares his weapon for grenade launching. Loading procedure:
• Load the SG 553 LB rie with standard, hardball ammunition.
• Set the safety lever to «S».
• Mount the rie grenade: it must be possible to twist on the grenade
up to the stop without encountering signicant resistance.
4.7.3 Aiming
At a range of 75 m (82 yds.), aim over the upper edge of the rie grenade
and the upper rim of the front sight tunnel. At longer ranges, cover
the target with the body of the grenade. Consequently, rst obtain the
height of the target by approaching it from the side. Then move the rie
sideways, without changing the inclination of the barrel, until the target
is covered.
Figure 42: Aiming the rie grenade
Range 75 m (82 yds.):
Point of aim = average point of impact
4.7.4 Launching positions
The grenade launching can be done from the standing, kneeling and
prone positions. The rie butt should be held as tightly as possible under
the armpit of the ring arm; the other hand grasps the handguard rmly.
Set the safety lever to position «1». Firing from the shoulder is also
possible. However, the trooper must take cover before the grenade
detonates upon impact.
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4.8 Use of accessories
4.8.1 Carrying sling
One end of the sling hooks into the lug on the front sight mount;
the other end is attached to the butt stock or the rear sight mount.
• To x the taut sling, use the clip.
• To maintain a taut sling, slip the clip over the sling strap.
Figure 43: Sling hooked to front sight
mount
Figure 44: Sling hooked to rear sight
mount
Figure 45: Fix the taut sling
Figure 46: Sling attachment to the
butt stock
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4.9 Field stripping
1. Unload the weapon in ac-
cordance with section
«3.3 Unloading» on page 47.
2. Unlock the carrying sling.
3. Press the rear trigger cas-
ing stud from both sides and
withdraw it from the stud
head side as far as the stop.
4. Lay the weapon on its left
side and swing out the trig-
ger assembly.
5. Witdraw the front trigger
casing stud as described in
point 3 and remove the trig-
ger assembly.
6. Press down the charging
handle catch and remove
the charging handle.
Figure 47: Remove trigger assembly
Figure 48: Remove charging handle
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7. Use the charging handle
to draw the bolt to the rear,
remove the bolt from the
receiver.
8. Twist the bolt head to
remove it from the bolt
carrier.
Figure 49: Draw bolt to the rear using
charging handle
Figure 50: Remove bolt head (rotate)
Figure 51: Remove bolt head (pull)
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9. Pull the lower handguard to
the rear and lift it off.
10. Lift the rear of the upper
handguard and extract it
from the front sight mount.
Figure 52: Lift off lower handguard
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11. Press down the gas valve
catch, remove the valve by
simultaneously rotating it
and pulling it out.
(Figure 53)
12. Remove the gas piston by
pushing it into the gas tube
and pull it out from the front
end. (Figure 54)
13. Press down the gas-valve
catch and rotate the gas
tube through 90° so that the
notch ange notch lies on
the barrel and pull out the
gas tube from the front. Figure 53: Remove gas valve
Figure 54: Remove gas piston
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14. Remove ring pin:
- Hold the bolt against a rm surface so that the ring pin is
completely pressed into the bolt head.
- Use the cleaning rod handle to remove the retention stud.
Extract the ring pin complete with spring.
Figure 55: Remove ring pin
15. Stripping the magazine:
- Use the cleaning rod handle to press in the retention lug of the
oorplate. Slide out the magazine oorplate to the rear.
- Pull out the oorplate catch together with magazine spring and
feeder.
Figure 56: Stripping the magazine
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16. If necessary, unmount the butt catch (not possible with some
models).
- Swing butt stock in folded position.
- Press down the butt catch with the charging handle and
turn it 90° counter-clockwise, take out the butt catch and
the spring
17. If necessary, remove the oorplate of the pistolgrip (take out the
loading tool).
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Figure 57: SG 553 SB Picatinny version stripped
Additional dismantling may only be performed by a weapons and equip-
ment mechanic.
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Figure 58: SG 553 SB Diopter version stripped
Additional dismantling may only be performed by a weapons and equip-
ment mechanic.
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Figure 59: SG 553 LB Picatinny version stripped
Additional dismantling may only be performed by a weapons and equip-
ment mechanic.
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Figure 60: SG 553 LB Diopter version stripped
Additional dismantling may only be performed by a weapons and equip-
ment mechanic.
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4.10 Assembly
The weapon must always be assembled in the reverse order of stripping:
1. Mount the oorplate of the pistolgrip (previously insert the loading
tool into the pistolgrip).
2. Insert the butt catch and spring into the butt stock, press down the
butt catch with the charging handle and turn it 90° clockwise.
3. Assemble the magazine.
4. Install the ring pin:
- Insert the ring pin and spring into the bolt head. Ensure that the
notch is correctly located to accept retention stud.
- Press the ring pin into the bolt head.
- When the notch aligns with the stud hole, insert the stud.
Figure 61: Install ring pin
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5. Install gas tube:
- Slip the gas tube (ange
notch pointing downwards)
through the bore of the
front sight mount and insert
the end into the correspon-
ding opening in the recei-
ver.
- Press the gas tube against
the front sight mount
and turn it through 90° to
the right so that the reten-
tion stud of the gas valve
registers in the ange.
6. Insert the gas piston with
recoil spring:
- Slide the gas piston, with
its retention notch facing
against the barrel, into the
gas tube.
- Check with the index nger
that the gas piston moves
freely in the tube.
(Figure 62)
Figure 62: Check gas piston position
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7. Install gas valve:
- With the notch for the catch
facing the barrel, insert the
gas valve into the headpie-
ce of the gas tube.
- Press in the gas valve
catch and rotate the gas
valve clockwise to setting
«I» (vertical).
- Check if the gas valve has
engaged.
8. Install the upper handguard.
9. Install the lower handguard.
10. Assemble the bolt head and
carrier.
11. Insert the bolt assembly:
- Move the bolt head completely to the front by pressing the ring
pin.
- Slide the bolt assembly into the receiver. (Figure 64)
Figure 63: Install gas valve
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Figure 64: Insert bolt assembly
12. Insert the charging handle into its slot in the bolt carrier and check
that it has registered with the catch.
13. Install trigger casing:
- Ensure that the holes in the front trigger casing overlap.
- Press the trigger casing stud through as far as the stop.
14. Tilt up the trigger casing and x it with the rear trigger casing stud.
15. Carry out function check in accordance with section
«4.11 Verication of Functions» on page 76.
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4.11 Verication of Functions
Each time the weapon is stripped, verify its functions as follows.
Sequence of Procedure:
1. Unload in accordance with section
«3.3 Unloading» on page 47.
2. Remove the magazine.
3. Check the serial numbers:
The last four digits of the serial number on the receiver casing
have to match the number on the bolt carrier, bolt head and trigger
casing.
4. Ensure that the cocking handle has registered in the correct
position.
5. Check the functions (a to f):
a) With the safety lever on «S» execute a loading cycle, pull
the trigger.
- The hammer must not drop, the trigger must be
blocked.
b) With the safety lever on «1», pull the trigger and hold it
back
- The hammer must drop.
With the trigger still held back, cycle the weapon once.
- The hammer must not drop.
Release the trigger and pull it again.
- The hammer must drop.
c) Execute a loading cycle.
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d) Set the safety lever to «3», pull the trigger and hold it back.
- The hammer must drop.
With trigger held back, cycle the weapon
(allow bolt to slide forward slowly).
- The hammer must drop immediately as the bolt locks
up.
Repeat the loading cycle.
- On the third loading cycle, the hammer must not drop.
Release the trigger.
e) With safety lever on «20», repeat procedure as under d)
- Hammer must drop each time.
f) Check the pressure point
Cycle the weapon:
- Set the safety lever to «1», verify several times that the
pressure point is discernible.
6. Insert an empty magazine, check that it is located rmly.
7. Check the bolt catch
a) Execute a loading cycle.
- The bolt must be caught in its rear position.
b) Push the bolt catch upwards.
- The bolt must immediately run forward.
c) Pull the trigger, set the safety lever to «S».
8. Check that the folded butt stock has registered.
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4.12 Procedure in case of malfunction
Whenever an SG 553 no longer works due to a malfunction, proceed
as follows:
• Carry out a loading cycle.
• Continue ring.
If the weapon does not re:
• Insert a fresh magazine and carry out a loading cycle.
• Continue ring.
If the weapon still does not re:
• Set the safety lever to «S».
• Remove the magazine.
• Loading action, hold the bolt in rearmost position, check ejection of
cases and, if necessary, remove any jammed cases or cartridges.
• Turn the gas valve on position II when the weapon is heavily fouled
or iced up.
• Insert a fresh magazine and carry out a loading cycle.
• Set the safety lever to desired ring mode, continue ring.
If the weapon still will not re:
• Set the safety lever to «S».
• Unload in accordance with section «3.3 Unloading (Clearing)» on
page 47.
• Clean the weapon in accordance with section
«5.1.2 Cleaning after ring» on page 81.
• Take up ring position.
• Insert a fresh magazine and carry out a loading cycle.
• Set the safety lever to desired ring mode, continue ring.
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If the weapon cannot be unloaded or the fault rectied by the rieman
in accordance with the operating instructions, a trained expert must be
consulted.
The following points must be borne in mind:
• If the weapon cannot be unloaded immediately and there is any
danger of self-ignition due to a hot barrel (140° C / 284° F), wait at
least 15 minutes.
• The weapon must remain in position as long as it is loaded.
• Spectators and other unnecessary persons must be sent away so
that the problem can be tackled carefully without disturbance.
• As long as the weapon is loaded, only trained experts should be
allowed to manipulate the weapon.
Malfunctions can largely be avoided by:
• Carrying out cleaning in accordance with section
«5 Maintenance» on page 80.
• Cleaning the weapon in accordance with section «5.1.2 Cleaning
after ring» on page 81 after each period of ring, at the latest just
after setting the gas valve to position II.
• Inserting the magazine correctly.
SG 553 Manual
80
MAINTENANCE 40 425 014
5 Maintenance
5.1 Types of maintenance
There are the following types of maintenance:
• Daily cleaning
• Cleaning after ring
• Cleaning after malfunctioning
5.1.1 Daily cleaning
Daily cleaning should be carried out if the weapon is dry and has not
been red.
Sequence of operations:
1. Unload the weapon
in accordance with section «3.3 Unloading» on page 47.
2. Clean the weapon externally
3. Lightly oil steel parts (to prevent rusting)
4. Carry out function check
in accordance with section «4.11 Verication of Functions» on
page 76.
5.1.2 Cleaning after ring
Sequence of operations:
1. Unload the weapon
in accordance with section «3.3 Unloading» on page 47.
2. Field strip the weapon
in accordance with section «4.9 Field stripping» on page 62
3. Clean and lubricate the weapon
as described in section «5.2 Cleaning and greasing» on page 83
4. Assemble the weapon
5. Carry out function check
in accordance with section «4.11 Verication of Functions» on
page 76.
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MAINTENANCE
40 425 014
5.1.3 Maintenance after malfunctioning
The SG 553 must be cleaned whenever the gas valve is switched to
position II. After cleaning, all moving parts should be lubricated and a
light coat of oil should be applied to all steel parts to prevent rusting.
Sequence of operations:
1. Set the safety lever to «S».
2. Unload the weapon in accordance with section
«3.3 Unloading (Clearing)» on page 47.
3. Press the rear trigger casing stud from both sides and pull it out
on the head side as far as the stop.
4. Tilt down the trigger casing, clean and check.
5. Remove the bolt assembly, clean and check.
6. Remove the gas valve, clean and check.
7. Remove the gas piston, clean and check for correct operation.
8. Clean the receiver casing.
9. Grease all parts in accordance with section
«5.2.3 Post-shoot lubrication instructions» on page 84.
10. Assemble the weapon.
11. Carry out function check in accordance with section
«4.11 Verication of Functions» on page 76.
12. Load the weapon and continue with assignment.
SG 553 Manual
82
MAINTENANCE 40 425 014
5.1.4 Actions to be taken in cold weather and snow
The weapon and ammunition are to be protected whenever possible
from ice build-up and snowfall. They are not to be stored in warm spaces
when outside temperatures are low because condensate could most
often build, which in the open air would lead to ice build-up.
• Hot shot weapons must not be dipped in the snow or submerged in
water because they can ice up once cooled down.
• At low temperatures the primed assault rie is carried with the butt
stock swung out.
• In case of iced-up diopter holes ring is carried out with the sight
open (100 m) and the corresponding hold point modied.
• To prevent ejection failures at low temperatures (from approx.
-10° C / 14º F) ring should be carried out right from the outset with
the gas valve position on the slant.
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SG 553 Manual
MAINTENANCE
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5.2 Cleaning and greasing
5.2.1 Greasing and degreasing
Sequence of operations:
1. Unload the weapon
2. Remove the bolt
3. Clean the barrel from the chamber down
5.2.2 Daily cleaning
• During daily cleaning the weapon should be wiped with a dry cloth
and the metal parts should be lightly lubricated.
5.2.3 Cleaning procedure
• Carry out the stripping procedure.
• Remove residual powder from the gas valve, gas tube and gas
piston with weapon cleaning oil.
• Clean the receiver and barrel from the rear.
• Clean the trigger assembly and all remaining parts of the weapon.
• Clean the accessories.
5.2.4 Lubrication procedure
• Lubricate the bolt and the barrel from the chamber down using oil.
• Lightly oil the valve and gas tube internally and externally.
• Lightly oil the gas piston and recoil spring.
• Lightly oil the trigger casing.
• Wipe all remaining metal parts with an oil cloth.
SG 553 Manual
84
FUNCTION 40 425 014
6 Function
6.1 General weapon function of SG 553
6.1.1 Readiness to re
At the moment of readiness to re the bolt is closed and locked. The
recoil spring (2) holds the bolt carrier (4) in the front nal position, via the
gas piston (1).
The bolt head (5) is rotated by the control cam (3) of the bolt carrier
(4) in such a way that its locking lugs (8) engage in the corresponding
recesses of the locking piece (9).
In this position the hammer (7) is cocked and the release bar (6) is
depressed.
Figure F1: Weapon loaded
(1) Gas piston
(2) Recoil spring
(3) Cam
(4) Bolt carrier
(5) Bolt head
(6) Release bar
(7) Hammer
(8) Locking lug
(9) Locking piece
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SG 553 Manual
FUNCTION
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6.1.2 Discharging the shot
By pressing the trigger (5) the hammer (3) is released.
The hammer is under pressure of the hammer spring (4) and strikes the
ring pin (2) which, in turn, impacts against the cartridge primer of the
cartridge (1) thus discharging the shot.
Figure F2: Discharging the shot
(1) Cartridge
(2) Firing pin
(3) Hammer
(4) Hammer spring
(5) Trigger
SG 553 Manual
86
FUNCTION 40 425 014
6.1.3 Unlocking and recoil of bolt
The gas pressure, generated by the burning powder, drives the
bullet through the barrel (4). As soon as the projectile passes the gas
port (5), propellant gas ows through the adjustable gas valve (1).
The gas pressure acts on the gas piston (2) which pushes the bolt
carrier (3) to the rear.
Figure F3: Unlocking and recoil of bolt
(1) Gas valve
(2) Gas piston
(3) Bolt carrier
(4) Barrel
(5) Gas port
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SG 553 Manual
FUNCTION
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During the rearward motion of the bolt carrier (3) the bolt head (2) is
rotated by the control cam (1) so that the locking lugs (4) are disengaged.
The bolt is now unlocked.
Figure F4: Unlocking begins
(1) Control cam
(2) Bolt head
(3) Bolt carrier
(4) Locking lug
SG 553 Manual
88
FUNCTION 40 425 014
The bolt assembly moves back along the rails in the receiver casing (2)
as far as the stop (4) whereby:
• the recoil spring (1) is compressed.
• the hammer (3) is cocked.
• the extractor (5) extracts the case from the chamber.
• the ejector (6) ejects the case through the port in the receiver
casing(2).
Figure F5: Case ejection
(1) Recoil spring
(2) Receiver casing
(3) Hammer
(4) Stop
(5) Extractor
(6) Ejector
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SG 553 Manual
FUNCTION
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6.1.4 Bolt advance
The force of the compressed recoil spring (1) thrusts the bolt forward.
The bolt head (2) feeds the next round from the magazine (3) into the
chamber.
Figure F6: Bolt advance
(1) Recoil spring
(2) Bolt head
(3) Magazine
SG 553 Manual
90
FUNCTION 40 425 014
In the nal stage of the advance, the bolt head (1) locks up and the re-
lease bar (2) is depressed.
The weapon is ready to be red.
Figure F7: Locking
(1) Bolt head (2) Release bar
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FUNCTION
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6.2 Trigger functions
6.2.1 General
Home position for describing the trigger functions:
• the hammer (3) is held by the trigger rod (4)
• the release bar (2) is depressed by the bolt carrier (1)
• the sear (5) is not engaged
Figure F8: Trigger mechanism in cocked position
(1) Bolt carrier
(2) Release bar
(3) Hammer
(4) Trigger rod
(5) Sear
SG 553 Manual
92
FUNCTION 40 425 014
6.2.2 Trigger in safe position «S»
• The safety lever (6) is set to «S»
• The safety shaft (7) locks the trigger (8)
Figure F9: Trigger in safe position «S»
(6) Safety lever
(7) Safety shaft
(8) Trigger
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FUNCTION
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6.2.3 Semi-automatic re
The safety lever (6) is set to «1» and the hammer (3) is held by the
trigger rod (4).
Figure F10: Trigger mechanism before ring
(3) Hammer
(4) Trigger rod
(6) Safety lever
SG 553 Manual
94
FUNCTION 40 425 014
By pulling the trigger (8) and after having overcome the pressure point,
the trigger rod (4) releases the hammer (3) which strikes the ring pin
(9). The trigger rod (4) falls downwards.
Figure F11: Striking the ring pin
(3) Hammer
(4) Trigger rod
(8) Trigger
(9) Firing pin
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SG 553 Manual
FUNCTION
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The recoiling bolt presses the hammer (3) down and releases the sear
(5) via the release bar (2). The sear (5) catches the hammer (3).
During the bolt advance, the bolt presses down the release bar (2). The
sear (5) is thereby moved to the rear and releases the hammer (3) to the
trigger rod (4).
When the trigger is released, the trigger rod (4) moves to its upper end
position (refer to g. F8).
Figure F12: Trigger mechanism during bolt recoil
(2) Release bar
(3) Hammer
(5) Sear
SG 553 Manual
96
FUNCTION 40 425 014
6.2.4 3-round burst control system
• The safety lever (6) is set to «3».
• The automatic re pawl (11) lies in the groove of the safety shaft
(7).
• The segment (10) is controlled by the safety shaft (7) and moved
upward.
Figure F13: Home position, 3-round burst
control system
(6) Safety lever
(7) Safety shaft
(8) Trigger
(10) Segment
(11) Automatic re pawl
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SG 553 Manual
FUNCTION
40 425 014
By pulling the trigger (8), the trigger rod (4) is withdrawn and simultaneously
retained by the automatic re pawl (11).
The segment (10) is pressed to the rear by the driving cam (12) in the
trigger (8) so that the pawl (13) is allowed to register.
Figure F14: Trigger mechanism, immediately prior to
ring
(4) Trigger rod
(8) Trigger
(10) Segment
(11) Automatic re pawl
(12) Driving cam
(13) Pawl
SG 553 Manual
98
FUNCTION 40 425 014
• When the hammer (3) is thrust forward, the chargeover (14)
presses the pawl (13) via its excentric (15) on the segment (10).
The segment (10) jumps up by one notch.
• The recoiling bolt cocks the hammer (3) which is retained by the
sear (5) (refer to g. F12).
Figure F15: Trigger mechanism after ring (rst round)
(3) Hammer
(5) Sear
(10) Segment
(13) Pawl
(14) Chargeover
(15) Excentric
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SG 553 Manual
FUNCTION
40 425 014
• The advancing bolt presses the sear (5) via the release bar (2) to
the rear thus releasing the hammer (3).
• The segment (10) moves up another notch.
Figure F16: Trigger system during ring (second round)
(2) Release bar
(3) Hammer
(5) Sear
(10) Segment
SG 553 Manual
100
FUNCTION 40 425 014
When the third round is red – just like the second round – via the
release bar, the segment (10), pressed by the chargeover (14) jumps on
the driving cam (12) of the trigger (8) and interrupts the support of the
trigger rod (4) by the automatic re pawl (11).
Figure F17: Trigger mechanism after the third round
(4) Trigger rod
(12) Driving cam
(8) Trigger
(11) Automatic re pawl
(14) Chargeover
(10) Segment
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SG 553 Manual
FUNCTION
40 425 014
• The sear (5) catches the hammer (3) (refer to g. F12).
• The advancing bolt drives the release bar (2) downward. The
release bar (2) presses the sear (5) to the rear and releases the
hammer (3) (refer to g. F16).
• The hammer is retained by the trigger rod. When the trigger (8) is
released the segment (10) moves back to its home position (refer to
g. F13).
IMPORTANT:
In order to ensure proper function of the 3-round burst control system,
pay attention to the following articles:
- During the complete 3-round burst, the trigger has to be fully
retained in its rearmost position.
- For each following 3-round burst, the trigger has to be released
in its foremost position and has to be pulled again.
SG 553 Manual
102
FUNCTION 40 425 014
103
SG 553 Manual
FUNCTION
40 425 014
6.2.5 Full auto re
The safety lever (6) is
set on «20».
The automatic re pawl
(11) which supports
the trigger rod (4) lies
in the groove of the
safety shaft (7).
By pulling the trigger
(8) the trigger rod (4)
is drawn to the rear
and supported by the
automatic re pawl
(11).
The hammer (3) is
released and strikes
forward (refer to g.
F2).The recoiling bolt
cocks the hammer (3)
which is retained by
the sear (5)
(refer to g. F12).
The advancing bolt presses on the release bar (2) which pushes the
sear (5) to the rear thus releasing the hammer (3) (refer to g. F16).
Figure F18: Trigger mechanism during full
auto re
(4) Trigger rod
(6) Safety lever
(7) Safety shaft
(8) Trigger
(11) Automatic re
pawl
SG 553 Manual
104
FUNCTION 40 425 014
• This trigger function is only interrupted when the trigger (8) is
released. In doing so the link between the automatic re pawl (11)
and the trigger rod (4) is disconnected.
• The trigger rod (4) moves downward and catches the hammer (3).
Figure F19: Interruption of fully automatic re
(3) Hammer
(4) Trigger rod
(8) Trigger
(11) Automatic re pawl
105
SG 553 Manual
FUNCTION
40 425 014
SG 553 Manual
106
APPENDIX 40 425 014
7 Appendix
7.1 List of gures
107
SG 553 Manual
APPENDIX
40 425 014
SG 553 Manual
108
APPENDIX 40 425 014
7.2 List of parts
7.2.1 Picatinny version,
short barrel
100 Receiver Group
111-A Receiver casing
141 Bolt cover (2x)
142 Bolt cover rivet (6x)
171-A Rear sight holder
172-A Rear sight plate
173-A Flat head screw
174-A Pressure plate
175-A Cup spring
176 Pin
200 Barrel/gas system
(picatinny version)
211-A Barrel SB
(short barrel)
212 Front sight mount *
213 Roll pin (2x)
214 Flash suppressor
223 Stop pin
224 Compression spring
225 Spring pin
231-A ip up front sight lower part
232-A ip up front sight
233 Positioning bolt
234 Night front sight spring
235 Spring pin
236 Front sight screw *
237 Front sight disc *
238 Spring pin
241 Gas valve
251 Gas tube
261 Gas piston
262 Recoil spring
263 Spring pin
268 Support washer
269 Gas piston bushing
271 Collar
300 Handguard
311 Upper handguard
321 Lower handguard
330 Picatinny rail **
331 Screw for Picatinny rail *
332 Washer for Picatinny rail *
333 Nut for Picatinny rail *
400 Bolt
411 Bolt head
412 Firing pin
413 Firing pin stud
414 Firing pin spring
415 Extractor
416 Extractor spring
417 Pin
421 Bolt carrier
422 Charging handle catch
423 Axle of charging handle catch
424 Spring of charging handle
catch
425 Charging handle
500 Trigger assembly
501 Trigger casing
510 3-round burst facility
511 Template
512 Chargeover
513 Pawl
514 Pawl spring
515 Bush
516 Segment
517 Segment axle
518 Segment spring
519 Locking washer
520 Compression spring
521 Magazine catch
522 Magazine catch spring
523 Magazine catch pin
524 Bush
531 Release bar
532 Circlip
541 Pistol grip
542 Floorplate
543 Allen screw
544 Stop nut
545 Nameplate
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SG 553 Manual
APPENDIX
40 425 014
551 Pressure point screw
552 Stop nut
553 Pressure point spring
554 Trigger guard
555 Trigger guard bearing
561 Hammer
562 Hammer axle
563 Main spring
564 Bolt catch
565 Bolt catch spring
566 Spring bolt
571 Safety lever
572 Safety shaft
573 Locking spring
575 Automatic ring lock axle
576 Spring pin
578 Stop ring
579 Automatic ring lock
581 Trigger
582 Trigger spring
583 Trigger rod
584 Pivot, trigger
585 Trigger bush
586 Trigger rod spring
587 Sear
588 Automatic ring pawl
589 Automatic ring pawl spring
591 Trigger casing stud
592 Spring-pressure pin
593 Spring for trigger casing stud
594 Spring pin
595 Pin
596 Cup spring
597 Bafe plate
598 Sear bolt
599 Sear roller
600 Butt Stock Group
611 Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
600-A Butt Stock Group
(Butt stock adjustable) **
611-A Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
617 Hinge
618 Detent insert
619 Spring pin detent insert (2x)
620 Cover
621 Locking pin
623 Axle of locking pin
624 Axle of adjusting latch
625 Circlip
626 Adjusting latch
627 Adjusting latch pressure
spring
628 Slider
629 Slider bolt
630 Slider compression spring
700 Magazine
711 Magazine casing
712 Magazine oorplate
713 Floorplate catch
714 Feeder
715 Magazine spring
* Cannot be ordered
as individual parts
** Optional
SG 553 Manual
110
APPENDIX 40 425 014
7.2.2 Diopter version,
short barrel
100 Receiver Group
111 Receiver casing
141 Bolt cover (2x)
142 Bolt cover rivet (6x)
151 Rear sight drum
152 Drum spring
153 Drum stud
154 Luminous ampules *
155 Insert
156 Rubber disc
161 Pivot
162 Drum axle
163 Spring washer
164 Safety washer
165 Leaf spring
171 Windage correction screw
172 Click stud
173 Rear sight spring
174 Limitation ring
175 Spring pin
181 Elevation correction screw
200 Barrel/gas system
(diopter version)
211-C Barrel SB
(short barrel)
212 Front sight mount *
213 Roll pin
214 Flash suppressor
223 Stop pin
224 Compression spring
225 Spring pin
231 Front sight
232 Night front sight
233 Positioning bolt
234 Night front sight spring
235 Spring pin
236 Front sight screw *
237 Front sight disc *
238 Spring pin
241 Gas valve
251 Gas tube
261 Gas piston
262 Recoil spring
263 Spring pin
268 Support washer
269 Gas piston bushing
271 Collar
300 Handguard
311 Upper handguard
321 Lower handguard
330 Picatinny rail **
331 Screw for Picatinny rail *
332 Washer for Picatinny rail *
333 Nut for Picatinny rail *
400 Bolt
411 Bolt head
412 Firing pin
413 Firing pin stud
414 Firing pin spring
415 Extractor
416 Extractor spring
417 Pin
421 Bolt carrier
422 Charging handle catch
423 Axle of charging handle catch
424 Spring of charging handle
catch
425 Charging handle
500 Trigger assembly
501 Trigger casing
510 3-round burst facility
511 Template
512 Chargeover
513 Pawl
514 Pawl spring
515 Bush
516 Segment
517 Segment axle
518 Segment spring
519 Locking washer
520 Compression spring
521 Magazine catch
522 Magazine catch spring
523 Magazine catch pin
524 Bush
531 Release bar
111
SG 553 Manual
APPENDIX
40 425 014
532 Circlip
541 Pistol grip
542 Floorplate
543 Allen screw
544 Stop nut
545 Nameplate
551 Pressure point screw
552 Stop nut
553 Pressure point spring
554 Trigger guard
555 Trigger guard bearing
561 Hammer
562 Hammer axle
563 Main spring
564 Bolt catch
565 Bolt catch spring
566 Spring bolt
571 Safety lever
572 Safety shaft
573 Locking spring
575 Automatic ring lock axle
576 Spring pin
578 Stop ring
579 Automatic ring lock
581 Trigger
582 Trigger spring
583 Trigger rod
584 Pivot, trigger
585 Trigger bush
586 Trigger rod spring
587 Sear
588 Automatic ring pawl
589 Automatic ring pawl spring
591 Trigger casing stud
592 Spring-pressure pin
593 Spring for trigger casing stud
594 Spring pin
595 Pin
596 Cup spring
597 Bafe plate
598 Sear bolt
599 Sear roller
600 Butt Stock Group
611 Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
600-A Butt Stock Group
(Butt stock adjustable) **
611-A Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
617 Hinge
618 Detent insert
619 Spring pin detent insert (2x)
(2x)
620 Cover
621 Locking pin
623 Axle of locking pin
624 Axle of adjusting latch
625 Circlip
626 Adjusting latch
627 Adjusting latch pressure
spring
628 Slider
629 Slider bolt
630 Slider compression spring
700 Magazine
711 Magazine casing
712 Magazine oorplate
713 Floorplate catch
714 Feeder
715 Magazine spring
* Cannot be ordered
as individual parts
** Optional
SG 553 Manual
112
APPENDIX 40 425 014
7.2.3 Picatinny version,
long barrel
100 Receiver Group
111-A Receiver casing
141 Bolt cover (2x)
142 Bolt cover rivet (6x)
171-A Rear sight holder
172-A Rear sight plate
173-A Flat head screw
174-A Pressure plate
175-A Cup spring
176 Pin
200 Barrel/gas system
(picatinny version)
211-B Barrel LB (long barrel,
ash suppressor integrated)
212 Front sight mount *
213 Roll pin
223 Stop pin
224 Compression spring
225 Spring pin
231-A ip up front sight lower part
232-A ip up front sight
233 Positioning bolt
234 Night front sight spring
235 Spring pin
236 Front sight screw *
237 Front sight disc *
238 Spring pin
241 Gas valve
251 Gas tube
261 Gas piston
262 Recoil spring
263 Spring pin
268 Support washer
269 Gas piston bushing
271 Collar
300 Handguard
311 Upper handguard
321 Lower handguard
330 Picatinny rail **
331 Screw for Picatinny rail *
332 Washer for Picatinny rail *
333 Nut for Picatinny rail *
400 Bolt
411 Bolt head
412 Firing pin
413 Firing pin stud
414 Firing pin spring
415 Extractor
416 Extractor spring
417 Pin
421 Bolt carrier
422 Charging handle catch
423 Axle of charging handle catch
424 Spring of charging handle
catch
425 Charging handle
500 Trigger assembly
501 Trigger casing
510 3-round burst facility
511 Template
512 Chargeover
513 Pawl
514 Pawl spring
515 Bush
516 Segment
517 Segment axle
518 Segment spring
519 Locking washer
520 Compression spring
521 Magazine catch
522 Magazine catch spring
523 Magazine catch pin
524 Bush
531 Release bar
532 Circlip
541 Pistol grip
542 Floorplate
543 Allen screw
544 Stop nut
545 Nameplate
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SG 553 Manual
APPENDIX
40 425 014
551 Pressure point screw
552 Stop nut
553 Pressure point spring
554 Trigger guard
555 Trigger guard bearing
561 Hammer
562 Hammer axle
563 Main spring
564 Bolt catch
565 Bolt catch spring
566 Spring bolt
571 Safety lever
572 Safety shaft
573 Locking spring
575 Automatic ring lock axle
576 Spring pin
578 Stop ring
579 Automatic ring lock
581 Trigger
582 Trigger spring
583 Trigger rod
584 Pivot, trigger
585 Trigger bush
586 Trigger rod spring
587 Sear
588 Automatic ring pawl
589 Automatic ring pawl spring
591 Trigger casing stud
592 Spring-pressure pin
593 Spring for trigger casing stud
594 Spring pin
595 Pin
596 Cup spring
597 Bafe plate
598 Sear bolt
599 Sear roller
600 Butt Stock Group
611 Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
600-A Butt Stock Group
(Butt stock adjustable) **
611-A Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
617 Hinge
618 Detent insert
619 Spring pin detent insert (2x)
620 Cover
621 Locking pin
623 Axle of locking pin
624 Axle of adjusting latch
625 Circlip
626 Adjusting latch
627 Adjusting latch pressure
spring
628 Slider
629 Slider bolt
630 Slider compression spring
700 Magazine
711 Magazine casing
712 Magazine oorplate
713 Floorplate catch
714 Feeder
715 Magazine spring
* Cannot be ordered
as individual parts
** Optional
SG 553 Manual
114
APPENDIX 40 425 014
7.2.4 Diopter version,
long barrel
100 Receiver Group
111 Receiver casing
141 Bolt cover (2x)
142 Bolt cover rivet (6x)
151 Rear sight drum
152 Drum spring
153 Drum stud
154 Luminous ampules *
155 Insert
156 Rubber disc
161 Pivot
162 Drum axle
163 Spring washer
164 Safety washer
165 Leaf spring
171 Windage correction screw
172 Click stud
173 Rear sight spring
174 Limitation ring
175 Spring pin
181 Elevation correction screw
200 Barrel/gas system
(diopter version)
211-D Barrel LB (long barrel,
ash suppressor integrated)
212 Front sight mount *
213 Roll pin
223 Stop pin
224 Compression spring
225 Spring pin
231 Front sight
232 Night front sight
233 Positioning bolt
234 Night front sight spring
235 Spring pin
236 Front sight screw *
237 Front sight disc *
238 Spring pin
241 Gas valve
251 Gas tube
261 Gas piston
262 Recoil spring
263 Spring pin
268 Support washer
269 Gas piston bushing
271 Collar
300 Handguard
311 Upper handguard
321 Lower handguard
330 Picatinny rail **
331 Screw for Picatinny rail *
332 Washer for Picatinny rail *
333 Nut for Picatinny rail *
400 Bolt
411 Bolt head
412 Firing pin
413 Firing pin stud
414 Firing pin spring
415 Extractor
416 Extractor spring
417 Pin
421 Bolt carrier
422 Charging handle catch
423 Axle of charging handle catch
424 Spring of charging handle
catch
425 Charging handle
500 Trigger assembly
501 Trigger casing
510 3-round burst facility
511 Template
512 Chargeover
513 Pawl
514 Pawl spring
515 Bush
516 Segment
517 Segment axle
518 Segment spring
519 Locking washer
520 Compression spring
521 Magazine catch
522 Magazine catch spring
523 Magazine catch pin
524 Bush
531 Release bar
532 Circlip
541 Pistol grip
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SG 553 Manual
APPENDIX
40 425 014
542 Floorplate
543 Allen screw
544 Stop nut
545 Nameplate
551 Pressure point screw
552 Stop nut
553 Pressure point spring
554 Trigger guard
555 Trigger guard bearing
561 Hammer
562 Hammer axle
563 Main spring
564 Bolt catch
565 Bolt catch spring
566 Spring bolt
571 Safety lever
572 Safety shaft
573 Locking spring
575 Automatic ring lock axle
576 Spring pin
578 Stop ring
579 Automatic ring lock
581 Trigger
582 Trigger spring
583 Trigger rod
584 Pivot, trigger
585 Trigger bush
586 Trigger rod spring
587 Sear
588 Automatic ring pawl
589 Automatic ring pawl spring
591 Trigger casing stud
592 Spring-pressure pin
593 Spring for trigger casing stud
594 Spring pin
595 Pin
596 Cup spring
597 Bafe plate
598 Sear bolt
599 Sear roller
600 Butt Stock Group
611 Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
600-A Butt Stock Group
(Butt stock adjustable) **
611-A Butt stock
612 Butt catch
613 Butt catch spring
614 Clip
615 Spring pin
616 Butt plate *
617 Hinge
618 Detent insert
619 Spring pin detent insert (2x)
620 Cover
621 Locking pin
623 Axle of locking pin
624 Axle of adjusting latch
625 Circlip
626 Adjusting latch
627 Adjusting latch pressure
spring
628 Slider
629 Slider bolt
630 Slider compression spring
700 Magazine
711 Magazine casing
712 Magazine oorplate
713 Floorplate catch
714 Feeder
715 Magazine spring
* Cannot be ordered
as individual parts
** Optional
SG 553 Manual
116
APPENDIX 40 425 014
117
SG 553 Manual
APPENDIX
40 425 014
7.3 Exploded drawings
Information to be supplied when ordering spare parts:
• Type of weapon
• Serial Number
• Caliber
• Item number
• Parts designation
SG 553 Manual
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APPENDIX 40 425 014
7.3.1 Exploded drawing / SG 553 SB
SG 553 SB Standard version with picatinny rail and
diopter sight
615
613
612
596
543
598 599
587
583
586
586
597 512
513
514
584
582
581
588
589
585
511
515
517 518
516
520 519
425
423 422
424
421
412
414
413
417
416
415 411
592
593
594
591
531
532 566
564
565
576
594
571
592
593
563
591575
595
561
562
573
501
578
579
571
576
572
553
552
541
544
542
545
551
555
554
523
524
521
522
711
712
713
715
714
111
175
142 141
321
211
213
212
225
224
223
237
238
236
232
233
234
231
251
241
261
263
311
262
268
213
235 510
269
271
222
332
333
333
332
330
331
614
616
611
171
174
164
165
181
161
173
172
153
152
155
151
154
163
162
156
214
119
SG 553 Manual
APPENDIX
40 425 014
7.3.2 Exploded drawing / SG 553 LB
SG 553 LB Standard version with picatinny rail and
ip up front and rear sight
615
613
612
596
543
598
599
587
583
586
586
597 512
513
514
584
582
581
588
589
585 511
515
517 518
516
520 519
425
423
422
424
421
412
414
413
417
416
415
411
592
593
594
591
531
532
566
564
565
576
594
571
592
593
563
591 575
595
561
562
573
501
578
579
571
576
572
553
552
541
544
542
545
551
555
554
523
524
521
522
711
712
713
715
714
111
176
175
174
171
172
173
142
141
321
211
213
212
225
224
223
237
238
236
232
233
234
231
251
241
261
263
311
262
268
213
235
510
269
271
221 222
332
333
333
332
330
331
614
616
611
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APPENDIX 40 425 014
7.3.3 Exploded drawing / Butt stock adjustable
620
615
617
612
613
619
618
611-A
614
629
621
623
625 628
624
626
627
616*
619
630
