SIG SG 516
SIG Sauer GmbH · Assault Rifle · In Production · 2010
Also known as: Sturmgewehr Model 516, SIG Sauer SIG516, SIG 516 LE/MIL
Overview
The SIG SG 516 is a select-fire assault rifle chambered in 5.56x45mm NATO, produced by SIG Sauer GmbH since 2010.
Specifications
| Weight (empty) | 3300 g (116.4 oz) |
| Weight (loaded) | 3870 g (136.5 oz) |
| Overall Length | 920 mm (36.22") |
| Barrel Length | 406 mm (15.98") |
| Sight Radius | 356 mm (14.02") |
| Action Type | Gas Operated Short Stroke Piston |
| Firing Mechanism | Hammer Fired |
| Trigger Type | Single Stage |
| Magazine Capacity | 30 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 905 m/s (2969 fps) |
| Muzzle Energy | 1640 J (1210 ft·lbf) |
| Effective Range | 500 m (547 yd) |
| Maximum Range | 3600 m (3937 yd) |
| Rate of Fire | 800 rpm |
| Barrel Rifling | Right Hand |
| Rifling Twist | 178 mm (7.01") |
| Number of Grooves | 6 |
| Frame Material | Aluminum Alloy |
| Barrel Material | Steel |
| Stock Material | Polymer |
| Finish | Hard Anodized |
Calibers
- 5.56x45mm NATO · primary · 5.56mm NATO — also known as 5.56x45mm, 5.56 NATO
Features
- Firing modes: Semi Automatic, Full Automatic
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Safety Selector, Four Position Gas Regulator, Firing Pin Safety
- Features: Short Stroke Piston System, Four Position Gas Regulator, Rotating Bolt, Flat Top Receiver, Picatinny Rail, M4 Feed Ramps, Forward Assist, Dust Cover, Cold Hammer Forged Barrel, Chrome Lined Barrel, Free Float Handguard, Folding Sights, Collapsible Stock, Ambidextrous Controls, Select Fire, Tungsten Buffer
Variants
- SIG SG 516 Patrol — Standard
- SIG SG 516 CQB — Short Barrel
- SIG SG 516 PDW — Personal Defense
- SIG SG 516 Precision Marksman — Designated Marksman
Base model
Service history
Operators
- Victoria Police Special Operations Group · as SIG 516
- Indonesian Mobile Brigade (Brimob) · as SIG 516 Patrol
- Turkish Police Special Operation Department · as SIG 516 Patrol
- UK Metropolitan Police Counter Terrorist Specialist Firearms Officers · as SIG 516
Production
Production years: 2010-present
Continuous production since 2010 with multiple generation updates. Select-fire variants produced for law enforcement and military contracts worldwide. Semi-auto civilian versions sold separately as SIG 516.
Origin
Country of origin: Switzerland
Designer: Robert Hirt, Chris Sirois
Notes
The SIG SG 516 designation uses the Swiss-German 'Sturmgewehr' (assault rifle) naming convention consistent with SIG's heritage (SG 550, SG 551, SG 553). The select-fire models are restricted to military and law enforcement sales only. The four-position gas regulator allows settings for normal, adverse conditions, suppressed fire, and off (converting to straight-pull bolt action). The PDW variant with a 7-inch barrel achieves a cyclic rate of 750-800 rpm. The platform served as a predecessor and stepping stone to the more advanced SIG MCX family. A 7.62x39mm 'Russian' variant was also produced for export markets.
Background
The SIG SG 516 emerged from a direct lineage to the HK416, as principal designer Robert Hirt had previously worked at Heckler & Koch on that platform before joining SIG Sauer. This pedigree gave the 516 instant credibility in the competitive gas piston AR market, though SIG's engineers made significant improvements including the distinctive four-position gas regulator that competitors lacked. The select-fire military models attracted attention from special operations and counter-terrorism units worldwide who valued the piston system's reliability advantage for suppressed operations. While the platform never achieved the widespread military adoption of the M4/HK416, its selection by multiple elite law enforcement units from Australia to Turkey validated its design philosophy. The 516's legacy lives on through the SIG MCX, which inherited many of its piston-driven principles while moving to a more modular architecture.