I've got a goal of putting together a silenced M1 Garand in .308. I'm in search of some help for obstacles I may encounter and a gunsmith interested in threading a barrel and headspacing it. The goal is to have a functioning M1 in .308 that accepts a YHM QD mount on the muzzle and cycles .308 rounds. I've purchased the rifle already and it runs fine on .30-06 so I'm happy with the action and internals. I've written in to the Silencer Co podcast and they answered my question, but weren't helpful in the assembly of the rifle. It was already done when they got it and didn't offer much on the way of how they put the SilencerCo qd mount on it. https://www.stitcher.com/podcast/bea...rms/e/59727842 14 minutes in for my question.
I've bought; Korea era M1 with new CMP wood, Criterion .308 24" barrel that needs finished reamed and headspaced on the rifle. A gas cylinder lock that needs cut a bit. An adjustable gas screw from Schuster MFG. And a QD mount in 5/8-24 for YHM silencers.
An issue I found already is the barrel isn't thick enough to support 5/8-24 threads. The gas cylinder lock slides over the muzzle and into the gas system, if I remember right the barrel is .516" in diameter. I think it will support 1/2-28 threading or 1/2-36 threading and YHM sells .30 cal QD muzzle brakes with both of those pitches. https://yhm.net/thread-specifications has drawings of threading that they require for the QD mounts. I've also found that that gas cylinder lock is too long to allow enough threads to be cut into the barrel. I have an extra that I purchased that I think can be cut to allow enough length for threading. In the picture below the muzzle on the left has a small shelf under it from the gas lock screw. I don't think that gas lock screw 'lip' actually contacts the barrel and needs to be present. If the lock screw can be cut then the barrel will have enough exposed to allow it to be threaded. I measured from the crown to the end of the gas lock screw and it was .670" long. From the muzzle to the lip of the screw was closer to 0.3" and much too short to allow it to have enough threads for a mount to be seated.
So, are there any suggestions on where to go to have a barrel that's off the rifle threaded? Then it'll need headspaced and finish reamed to .308. There's very little documentation about the few rifles that others have done but apparently it can be done and I'd like to do it.
I've bought; Korea era M1 with new CMP wood, Criterion .308 24" barrel that needs finished reamed and headspaced on the rifle. A gas cylinder lock that needs cut a bit. An adjustable gas screw from Schuster MFG. And a QD mount in 5/8-24 for YHM silencers.
An issue I found already is the barrel isn't thick enough to support 5/8-24 threads. The gas cylinder lock slides over the muzzle and into the gas system, if I remember right the barrel is .516" in diameter. I think it will support 1/2-28 threading or 1/2-36 threading and YHM sells .30 cal QD muzzle brakes with both of those pitches. https://yhm.net/thread-specifications has drawings of threading that they require for the QD mounts. I've also found that that gas cylinder lock is too long to allow enough threads to be cut into the barrel. I have an extra that I purchased that I think can be cut to allow enough length for threading. In the picture below the muzzle on the left has a small shelf under it from the gas lock screw. I don't think that gas lock screw 'lip' actually contacts the barrel and needs to be present. If the lock screw can be cut then the barrel will have enough exposed to allow it to be threaded. I measured from the crown to the end of the gas lock screw and it was .670" long. From the muzzle to the lip of the screw was closer to 0.3" and much too short to allow it to have enough threads for a mount to be seated.
So, are there any suggestions on where to go to have a barrel that's off the rifle threaded? Then it'll need headspaced and finish reamed to .308. There's very little documentation about the few rifles that others have done but apparently it can be done and I'd like to do it.