A.R.M.S. #41 gas block/flip-up front sight
The A.R.M.S. #41-B-L Silhouette is a combination gas block and flip-up front sight. The current version is only available for gas block seats with the standard 0.750” diameter. The gas block/sight is referred to as the “Silhouette” because when the sight is in the up position, the Silhouette retains the same “A-frame” outline as that of a standard A2 front sight base. This version of the Silhouette also has the familiar bayonet lug and attachment points for a standard sling swivel. The Silhouette weighs 6 ounces as pictured below.
The #41-B-L is secured to the barrel via two cross bolts. The #41-B-L also comes with a 0.027” shim that takes the place of the handguard end-cap when using a free-float tube. This makes positioning of the #41-B-L a breeze. While the sight is not stamped as such, it is an “F” marked front sight base; that is, the shelf for the front sight post sits 1.980” above the top of the barrel at the gas block seat.
Colt A2 with standard front sight base
Colt A4 with the A.R.M.S. #41-B-L Silhouette