The Suppressor Alignment Gage (SAG) is a precision gauge used to verify the alignment of a suppressor to the bore of a firearm barrel. The Alignment Gauge is marketed jointly by Surefire and by Geissele.
It is important to understand that the length of the suppressor is usually much longer than the length of the barrel / muzzle device / suppressor interface geometry. A small deviation at the mounting interface means a much larger deviation of the suppressor exit hole. The deviations from nominal can also be additive, which compounds suppressor misalignment.
The Geissele SAG is manufactured from hardened steel that has been ground 0.002” under nominal bore diameter. The outside diameter of the SAG is finely finished and straight to 0.001” over its length. Geissele hardens the SAG so that it will not wear by sliding exposure to abrasive powder residue, pull burrs if it slides against misaligned baffles nor allow abrasive particle to embed into the surface of the gauge.
At Charlie's, we have had a number of folks call us and comment online telling us they have found a rod cheaper at an industrial supply store, or at a big box hardware store, or that they do not need a rod, they just shoot. We get it, these are expensive. You can ride around in your car without a seatbelt, and probably not get hurt. Probably that rod in the Aisle 8 will work. But, when probably knocks a hole in your suppressor, that is not a good thing. And, even if the manufacturer replaces a busted can. Now, you are out the time to file a new Form 4 and possibly another tax stamp. If you cannot afford the right tools for the job, borrow a friends tool, or take your suppressor to an armorer to get it checked.
There can be a wide variation in barrel bore diameters and bore straightness. 0.002” under nominal bore diameter has been found to be the best size of the SAG that will fit most barrels. The long length of the SAG aligns the gauge to the bore; it is not necessary to have a very tight-fitting gauge with the long length of the Geissele SAG.
Get It Right The First Time. SureFire Bore Rods are valuable tools that will ensure proper concentricity along the bullet flight path when firing suppressed on a new platform. The rod most closely represents the bullet flight path and will show any misalignment, if present. SureFire recommends that operators verify barrel-to-adapter-to-suppressor alignment on any new build or any previously unshot setup, and SureFire Bore Rods are the most effective way to confirm it. Simply choose the corresponding rod for your caliber rifle or carbine.
Note: The alignment rod may come branded by Geissele or by Surefire.
