By adjusting the volume of gas in the cylinder it changes the speed of the op-rod and controls the harmonic vibration of the barrel. Even if you only shoot your M1 once in a while make it last a second lifetime. Our plug softens the blows on your op-rod and wear on the bolt lugs. Made from Hardened Tool Steel & Parkerized.
READ THIS FIRST: Unload firearm before making any adjustments! You will notice that the setscrew in the Gas Plug may be very tight and will not easily turn by hand. Once installed in the rifle it will become much easier. The setscrew comes at a factory set position, air will easily blow through it. The rifle WILL NOT FUNCTION at this position. Use it as a starting point, then screw in as necessary until rifle begins to function.
Installation: Remove existing gas plug, and replace with your new adjustable gas plug. Start with setscrew at the factory preset position. Turning the screw about ¼ turn at a time, tighten screw, and fire until the rifle functions reliably with your particular load. If the adjusting screws seems to loosen , install the hollow locking setscrew and tighten against the original screw locking it in place. Locating your Rifle’s sweet spot requires some trial and error. Once rifle is functioning properly, try turning the setscrew 1/8 of a turn at a time and fire a few rounds. Repeat until best group is found. Some shooters like to scribe a small line on the setscrew itself, and use it as a marker for identifying plug position (i.e. 3 o clock).
*Since handloading operations are beyond our control, we disclaim all liability for any damages which may result.
Need a replacement for the locking set screw? Get one here:Replacement Screw for M1A Gas Plug
Posted by Unknown on 29th Mar 2017
After finding I can shrink group size by half or better, having another m1a in the rack requires another adjustable gas plug. Dollar for dollar you cant beat a Schuster.
Posted by Unknown on 2nd Dec 2016
Put 100 rounds through the M1A so far. The plug is turning out to be quite reliable. For the price these rifles are going for these days, the plug is an investment in longevity. Would recommend this plug to anyone wanting to save their rifle from unnecessary abuse. BTW, the complimentary candy road kill would make a better refrigerator magnet.
Posted by Unknown on 26th Jul 2016
I installed this plug on a short barreled (18") M-1A to shot heavy bullets and perhaps use slower powders. It took all of 5 shots to get it dialed in. Function is definitely smoother, ejection not as violent, and the fit and finish on the plug is well done.