Sig Sauer SIG551A1 5.56 NATO Semi-Auto Rifle, 16 in CHF Threaded Barrel, Swiss Gray, Folding Skeletonized Stock, Diopter Sights, 6x 30-Round Mags
The Sig Sauer SIG551A1 delivers the classic 55x pattern in a US-made, collectible configuration with a Swiss gray aluminum-alloy receiver. It features a 16-inch cold hammer forged steel barrel with a 1:7 twist and 1/2x28 threads capped by a factory flash suppressor. A receiver-length M1913 Picatinny rail, rotary diopter rear sight, protected front post, and a folding skeletonized stock round out a practical, well-equipped package. This rifle comes with six translucent 30-round 55x-pattern magazines and the original case.
Condition
Overall Condition: Good condition, showing some signs of prior use and handling.
Bore Overall Condition: Good - Clean, well-maintained, minor wear marks.
Bore Rifling: Good Rifling - Intact, well-defined lands and grooves.
Specific Condition Notes: There are some scuffs and wear from prior handling and use. It appears to function well.
What’s Included
- Original case
- Six 30-round translucent polymer 55x-pattern magazines with side-coupling studs
Built in the USA and rollmarked "SIG551A1, 5.56 NATO, SIG SAUER INC., EXETER, NH, USA," this model captures the sought-after 55x lineage in a Swiss gray finish. The aluminum-alloy receiver and matching finish deliver a cohesive, authentic look while keeping weight in check.
The 16-inch cold hammer forged steel barrel uses four-groove rifling and a 1:7 twist to stabilize a broad range of 5.56mm projectiles. It is threaded 1/2x28 and fitted with a factory flash suppressor. The gas-piston, rotating-bolt action provides reliable cycling with 5.56mm NATO.
Sighting is handled by a protected front post integrated with the gas block and a rotary diopter rear drum marked "300." A receiver-length M1913 Picatinny rail provides a solid mounting surface along the top of the action. Polymer 55x-pattern ribbed handguards with cooling slots manage heat and maintain the classic profile.
Controls include a paddle-style magazine release and a right-side bolt-catch button, with a manual two-position safety. The Swiss 55x-pattern folding skeletonized stock offers compact storage and a 13.25-inch length of pull. Capacity is 30+1, and this rifle ships with six translucent 30-round magazines featuring side-coupling studs, plus the original case.