Jump to content

Recommended Posts

I have a 14-1/2" Green Mountain barrel that I hope to one day put on a 1927A1 AO. The AO compensator screws on just fine. What's bothering me some is the pin and welding business that I'm told the ATF requires. Is there any other way to do it that you guys know of that still satisfies the ATF.

Link to comment
Share on other sites

I have heard of three ways that people permanently attach muzzle devices to barrel to bring their overall length to the necessary length to avoid it becoming an SBR. The first option that I have heard of is drilling a blind hole through the muzzle device and into the barrel, use a hardened pin or section of drill bit to put in the hole, and then welding the top of the pin/hole. The second option is welding the muzzle device around the entire circumference of the barrel & muzzle device to permanently fuse them together. The last option that I have heard about is using a high temp silver solder (about a 1300 degree F melting point) and soldering the compensator to the barrel. I would recommend verifying those options though, but those are the ones that I have heard of.
Link to comment
Share on other sites

Several years ago I did what you are doing, with a Green Mountain Barrel.

But I first had the Barrel Blank Adapted before Welding the Cutt Compensator on

After making sure I had the Proper Length of 16.5 Inches from the end the Cutt Comp to the Breech* with the Bolt Closed, I took a thin Wooden Dow placed it in the Barrel, marked the dow (red magic marker) it at the end of the Cutts.

Then measure the Wooden Dow to make sure proper Legal Length. Took Cutts Comp off.

I put some mild Loc Tight on the thread, put the Cutts back on, tried to line the Front Sight as best as possible with the end of the Cutt to the Red Line on the Wooden Dow.

Then after Loc Tight set, I had it Welded all the way around the Cutts and the Barrel.

Blued the whole thing with Brownells paste bluing, looks good and can easily put Blank Adapt Plug in with Allen Key down the Cutts.

I have a Quick Disconnect Barrel System so I can easily change with the Original 16in Barrel or Plugged 10.5 Barrel for static display at WW2 Reenactments.

My long term plan is to have a custom Horizontal Foregrip made that is slightly longer, maybe 1.5 to 2 inches,so the 14.5 Barrel doesn't look strange.

 

*ATF measures Barrel from the Breech to the end of the Barrel's Muzzle.

I keep the red marked Wooden Dow and a small Tape Measure in the Gun Case....in the event ATF are spying on WW2 Reenactments for any illegal weapons.

Edited by jojeep
Link to comment
Share on other sites

Thanks for the replies fellows,jojeep,I hope to do what you did concerning the quick disconnect and the longer forend. I would tend as of now to go with a spot weld over the pin on the comp. There's a gunsmith here that can do the drilling for the pin, and can do hot bluing,but will be up to me to do the spot weld.

Link to comment
Share on other sites

In my opinion, the Cutts visually emphasizes the long length of the 16 1/2" barrel.

 

I bought a front sight from Kahr and Crazy-glued it to the compensator threads.

 

Looks good and the barrel doesn't "appear" as long as it actually is. ...Phil

Link to comment
Share on other sites

 

Thanks for the replies fellows,jojeep,I hope to do what you did concerning the quick disconnect and the longer forend. I would tend as of now to go with a spot weld over the pin on the comp. There's a gunsmith here that can do the drilling for the pin, and can do hot bluing,but will be up to me to do the spot weld.

Link to comment
Share on other sites

I did the Quick Disconnect Barrel System using a Tap I purchased from Doug Richardson. I can't remember the Thread Size.

It allowed me to use a Horizontal Foregrip Screw to hold the whole thing together.

You have to remove the Barrel, and Grip Mount.

File the Grip Mount so it slides into the Receiver, but is not loose. Then you Drill through both. Only the Receiver gets Taped for Threads. I took the Grip Mount to a Machine Shop and had them Counter Sink so the Horizontal Foregrip Screw sits flush.

Also a small notch must be put into the Barrel Threads so it all locks together.

This is just a High Lite of what the Quick Disconnect Barrel System is like....you need to take your Time or if you are friends with a Machinist or Gunsmith a End Mill can be used to bore into the Barrel Threads and the Horizontal Foregrip Screw turned Down to like a Round Peg ina Round Hole.

I should one day post photos of the whole thing here.

Edited by jojeep
Link to comment
Share on other sites

I've seen a picture of a grip mount that has one screw, and another that used two through the grip mount (don't remember where, probably on here somewhere). The gunsmith here is more than capable of drilling and tapping the receiver and drilling mount. I wonder if a setup of having the barrel screw on hand tight to a hard stop is inferior to maybe having a slight torque on the barrel to a hard stop. Any chance of those screws working loose from heat or vibrations?

Link to comment
Share on other sites

I seen 1 quick change system where the handguard mount slid out with a spring loaded catch that hooks the back of the barrel and when pressed up towards the chamber the other end moved out of the way and could be slid out.The barrel was only hand tight and the lock on the grip bar kept the barrel from rotating.I havent seen another i would love to find a grip bar barrel combo for the setup but havent seen them offered anywhere.If somone has one they should loan it to Reconbob or somone who can replicate it.
Link to comment
Share on other sites

I see now that I must have been dreaming about 2 screws thru the grip mount an into the barrel threads, it looks like there's only enough room for 1. Barrel only appears to go about 1/2" into receiver.

Link to comment
Share on other sites

@Burgernut, dug it out to take some quick pictures to give you a rough idea. I practiced on the nose piece from a Full Auto parts kit I purchased 20 yrs ago.

The Key thing is gets the correct Tap and Die to Tap the Receiver and clean the Threads on the Cut Down Horizontal Foregrip Screw. When I first came across this method of doing a Quick Disconnect Barrel System, it was stress to use that Tap/Die so all threads match on the Firearm. I can't remember the Size, it is a uncommon size used today......but someone online probably sells them, I got the Tap/Die Set early 2000's from the now late Doug Richardson....someone on this Forum will know the Size Tap/Die to purchased and keep with you Thompson Tools.

Sorry that I can't find mine to give you the size, probably in a Box packed in my Garage somewhere. Hope the Photos give you and Idea,

how its done.

 

PS: The Article I read late 1990's explains this Quick Disconnect Barrel System was supposedly going to be incorporated in the Original 1921 TSMG, but the Engineering Dept decided it was not necessary. If it had been incorporated when disassembled, the Barrel, Receiver and Buttstock were all about the same Length

post-258532-0-34811800-1664391262_thumb.jpg

post-258532-0-04262400-1664391355_thumb.jpg

post-258532-0-98322900-1664392241_thumb.jpg

Edited by jojeep
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...