Sig Sauer SIG 556 5.56mm NATO Semi-Auto Rifle, 16 inch Barrel, Long-Stroke Gas Piston, Folding Sights, Magpul ACS Stock, Picatinny Top Rail
This U.S.-made Sig Sauer SIG 556 pairs the proven SG 550 lineage with a long-stroke gas piston, a rotating bolt, and a two-position adjustable gas regulator. It features a 16 inch threaded barrel with a flash suppressor, folding iron sights, a full-length Picatinny top rail, and AR-15/STANAG magazine compatibility. This example is fitted with a Magpul ACS collapsible carbine stock and is marked Exeter, New Hampshire on the receiver.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: There are a few minor scuffs visible on the exterior surfaces, but the rifle remains in great shape.
What's Included
- Sig Sauer SIG 556 rifle with Magpul ACS carbine stock (installed)
- 1x 30-round Magpul PMAG polymer AR-15/STANAG magazine (5.56×45)
Built as a U.S. commercial adaptation of the Swiss SG 550 family, the SIG 556 uses a long-stroke gas piston with a rotating bolt for reliable cycling. A two-position adjustable gas regulator allows quick tuning for different conditions and ammunition.
The 16 inch barrel is threaded and topped with a flash suppressor. Controls include a right-side reciprocating charging handle and a manual safety. The receiver is aluminum alloy and carries an Exeter, New Hampshire production marking.
Sighting equipment consists of a folding hooded front sight mounted on the gas block and a folding aperture rear sight on the receiver rail. A full-length Picatinny top rail runs the length of the receiver for mounting compatible accessories.
Furniture includes a two-piece polymer ribbed handguard with ventilation slots and a SIG-pattern textured polymer pistol grip. The installed Magpul ACS collapsible stock with friction lock provides solid shoulder support, with a listed length of pull of 14.0.
The rifle feeds from AR-15/STANAG pattern magazines and has a 30+1 capacity. One 30-round Magpul PMAG is included.