SIG 556

With all the excitement following the poor showing by the M4 versus three piston-powered challengers in Army testing, it’s worth looking at some other piston ARs out there. There are a lot of them, and more are on the way.

For those of you who missed it, here are the results of the US Army’s recent “sandstorm test” pitting the M4 carbine against the Heckler & Koch HK416, the FN USA Mk16 SCAR-L, and the Heckler & Koch XM8:

sandstorm test m4 scar hk416

As you can see, the Colt’s M4 was the clear loser. Colt has two piston models ready to go, and most manufacturers are rushing their own models off the drawing board.

David Crane takes a look at the SIG 556 SWAT. With pictures and commentary.

Here is the standard SIG 556:


Caliber: 5.56mm NATO
Overall Length: 37.0″
Length w/ Stock Collapsed: 33.5″
Barrel Length: 16″
Rifling: 1 in 7″
Sight Radius: 21″
Forearm: Polymer SIG TriRail
Weight w/o Mag: 7.8 lbs
Operating System: Gas Operated, Rotating Bolt
Mag Capacity: 30 Rounds
MSRP: $1,299.95