SG 550 FUNCTION PRINCIPLE

Indirect gas operation with rotating bolt is rugged and functionally dependable. It reduces the recoil to a minimum and guarantees the function even under the most extreme service conditions. Gas operation is not sensitive to various types of ammunition, varying gas pressures and different case materials. Maximum safety for the shooter as premature unlocking of the bolt through overpressure is not possible.

The gas pressure of the rifles can be regulated if the weapons are heavily fouled. The indirect gas operation prevents the bolt and receiver housing from fouling by propellant gases. The gas system can be removed as a complete assembly that is easy to clean. No exaggerated cyclic rate (excess energy); hence, lower stress levels of the weapon and better control during fully automatic fire.
 		    
  SG 551 Swat

 

A gas-operated weapon system of minimal size and weight that is designed for SWAT team tactical missions. It is highly suitable for any military engagement, especially maritime operations, as well as demanding law enforcement. Options include an adjustable drum dioptre sight or Picatinny rail receiver with adjustable auxiliary iron sights. The long barrel model is designed for shooting rifle grenades and has a bayonet option.


Barrel length
Two versions are available: SG 551 with standard barrel length and SG 551 LB with an extra long barrel. The SG 551 LB is designed with a bayonet option.

    


Picatinny accessory rail adapters
The rifles can be outfitted with different tactical equipment, such as quick detachable Picatinny accessory rail adapters for mounting a vertical fore-grip and/or bipods.
Upper fore-grip with Picatinny rails on both sides to mount tactical lights are also available.


GL 5140
SG 551 can be equipped with the 40 mm Grenade Launcher GL 5140.
 
  TECHNICAL DATA
SG 551 LB (Long Barrel) / SG 551 		         
 
Caliber
5,56 mm (.223 Rem.)

Overall length
924 / 833 mm; 36.4 / 32.8”

Overall height
210 mm, 8.27“

Length with butt stowed
698 / 607 mm; 27.5 / 23.9“

Barrel length
454 / 363 mm; 17.9 / 14.3“

Rifling
178 mm (7”),
254 mm (10”)

No. of grooves
6

Sight radius
466 mm; 18.35”

Weapon weight
3,6 / 3,4 kg; 7.94 / 7.5 lbs.
 		  
Magazine capacity
5, 10, 20, 30

Mag. Weight with 20, 30 rounds
340, 480 g; 11.99 , 16.93 oz.

Combat weight with 120 rounds
5,6 / 5,4 kg; 12.35 / 11.90 lbs.

Weight of empty mag. 20, 30
95, 110 g; 3.35, 3.88 oz.

Trigger pull weight
35 N (3,5 kg), 7.72 lbs.

Muzzle energy
1600 / 1460 J

Cyclic rate
approx. 700 rounds/min

Function principle
Gas operated

Bolt pattern
Rotating bolt