SIG SAUER® Begins U.S. Production of Classic 550-Series Rifle
Published Date: 1/26/2012
SIG551-A1™ brings the legendary firearm to the American market for first time in decades
EXETER, NH (January 2012) — Long sought after by American collectors, the Swiss Arms SG 550-
series rifles have been a mainstay of European militaries for the past three decades. Now that same
reliable operating system and distinct Swiss styling has once again returned to the American market with
the introduction of the SIG551-A1 rifle.
“Without a doubt, the rifle we are most often asked about is the SG 550-series,” said Ron Cohen, SIG
SAUER President and Chief Executive Officer. “There has always been a steady stream of requests
asking us to manufacture the rifle domestically.”
The SIG551-A1 is a semi-automatic, American-built version of the SG 551 currently in service with the
Swiss army. An adjustable gas piston operates a rotating bolt, giving long service life and reliable
operation in the most unforgiving environments.
A genuine Swiss forearm, folding buttstock, and distinctively translucent curved magazine give the
SIG551-A1 its original look. The upper and lower are done in a grey hard coat anodized finish, similar to
the original SG 550-series in appearance.
Chambered in 5.56mm NATO, the SIG551-A1 uses original Swiss polymer magazines, which can be
attached together with molded-in connection points. An M1913 Picatinny top rail allows the operator to
mount any number of optics. Included is a rotary diopter sight, calibrated from CQB distances out to 300
The 16” barrel has four-groove, 1:7 twist rifling for exceptional accuracy and features the trademark 550-
series flash suppressor. A two-position gas system keeps the SIG551-A1 operating, even in substandard
A short-barreled version is planned for the factory SBR program in the near future