"Accidentally" Removed my 1928AC Thompson Barrel

[Sandman1957]

I have a new one for you... after firing my 1928AC this weekend, started cleaning it tonight and saw that the Cutts Compensator was a little loose. Most likely has been like that but since I had it torn apart, grabbed a punch to remove the Compensator. Note, I did not have this in a vice. I simply punched out the cross pin and with a cushioned set of pliars tried to remove the Cutts. It would not budge, so I put the front sight back on, and with the same padded pliers, held down the reciever on the edge of my table and started screwing off the cutts compensator, Once I got the cutts off, I noticed that the barrel had also come out about a 1/4 of an inch or more. So I got a piece of oak triangle to use to keep the front grip mount from hitting the fins and removed the barrel. The barrel threads do not look very well. there are no markings on the barrel, so I think it is an aftermarket West Hurley barrel.

 

Taking photo's now. Will post them shortly. Needless to say, I do not feel qualified to put the barrel back on, nor do I want to put this barrel back on until someone takes a good look at the barrel threads. I do have some other parts kit barrels that I can choose from.

 

If you used to own this 1928AC and had the barrel replaced or if you did it yourself, please chime in as I am always trying to document previous owners etc. It was a 1928AC I picked up from David Spiwak in 2014. AO152547x. Reciever and lower match, even has AO154547x under the barrel. All internals are AO marked.

 

The gun runs great and is my favorite shooter.

 

Semper Fi

Sandman1957

Edited September 1, 2015 by Sandman1957

[DZelenka]

A friend just pulled a barrel on a parts kit. It didn't come off very easily.

[Sandman1957]

Photos of lose barrel after taking off the Cutts Comp.

Edited September 1, 2015 by Sandman1957

[Sandman1957]

I'll try and take a close up of the gooned up threads, and the SN under the barrel hanger.

 

Did AO put these numbers under the barrel, or did someone do that then the barrel was changed out? Assuming an unmarked barrel is likely to be a WH barrel.

Edited September 1, 2015 by Sandman1957

[m60mgman]

I'll try and take a cross up of the gooned up threads, and the SN under the barrel hanger.

 

Did AO put these numbers under the barrel, or did someone do that then the barrel was changed out? Assuming an unmarked barrel is likely to be a WH barrel.

AO put the secret number under the grip mount.

 

The first 1000 also had the number on the barrel, breech end.

 

Tracie Hill's Ultimate Thompson book has all this info in it, well worth the money for a great reference.

[Sandman1957]

I knew Colt did that on the guns under contract for Auto Ordnance. Didn't know AO continued that into the war. First time I have taken off a barrel, and in this case did not intend to. Once it was loose, just decided to take it all the way off.

[giantpanda4]

Yes, the "secret" number is on many WWII guns too.

[gijive]

Sandman,

 

When you refer to under the barrel are you referring to the grip mount slot on the receiver? If so, yes both Savage and AO stamped the serial number of the receiver in this location during WWII. I find it interesting that your "secret" serial number also has the X suffix in that location. This is just more evidence that Maguire industries built these guns from remaining parts after WWII. If the gun had been whole during WWII production, it would be unlikely that the X would have been added to the "secret" location.

[buzz]

If that was my gun it would be sent off to reconbob for a NOS barrel.

 

a barrel install is a job for an expert, IMHO

Edited September 2, 2015 by buzz

[buzz]

dzelenka, why did your friend ruin that barrel?

 

was it pitted or shot out?

[DZelenka]

dzelenka, why did your friend ruin that barrel?

 

was it pitted or shot out?

It was on a parts kit. I had used the compensator to replace my unmarked one and sold the rest of the parts kit to him (he is an 02/07) for what I paid for it. Free compensator and wood to me yea. The barrel had been demilled with a rod and was saw cut. He said he had a heck of a time unscrewing it even after removing the rod. He would have been more careful if it had been a usable barrel but did say he will likely send future Thompson barrel work to a shop with the correct tools.

 

Dan

[reconbob]

_{If the barrel has worked loose, and if you can see that the threads are "gooned" up I cannot}

_{imagine why you would want to put this barrel back on the receiver. You say the gun is a shooter}

_{so I don't think putting a new barrel on - if its an original barrel - would do any harm to the}

_value.

_{The square thread is not a good thread for holding pieces tightly together (as opposed to a}

_{V-thread) and the barrel may have worked loose because of what appears to be a defective thread.}

_{If you torque the existing barrel on nice and tight it will turn on a little farther than it did before}

_{and you will have to re-position and re-pin the comp. But if the existing pin hole is only slightly off}

_{the new hole will be so close to it that the pin will probably not hold the comp tight.}

 

_Bob

 

[mnshooter]

Did you measure the diameter of the barrel fins at the rear?

GI barrels are once inch. West Hurley is usually .990 or less.

[Sandman1957]

Right now, I do not intend to put the same barrel back on. I do have some NOS from parts kits and will likely pick the best one. I don't have calipers here in my apt, but will check the thread size when I go home this weekend. Very likely Recon Bob has a barrel job on the horizon. That way he can check out the rest of the gun as well.

 

Gijive, great insight on the x in the front grip slot. Tried to take several photos for interest. Like the one sans barrel, showing the end of the bolt. Don't see that view often. Enjoy.

Cheers

Sandman1957

 

[TD.]

The commercially sold 1928AC Thompsons by the Auto-Ordnance Corporation and/or the Auto-Ordnance Division of Maguire Industries from approximately 1943 to 1946 were basically parts guns. There was no standardization of parts. These guns were assembled or manufactured starting with the left over parts from the 1928 production line at the Auto-Ordnance Bridgeport plant. Any World War II barrel would be correct. Most of the original AC guns I have seen over the years have smooth barrels and the L type rear sight. It is possible a previous owner of A.O. 152547x added the finned barrel to your AC Thompson; same with the Lyman adjustable rear sight. If your AC Thompson has been refinished, it is likely these possible "upgrades" happened during this process.

 

I think you are wise to ship the entire gun to reconbob for his evaluation and a proper barrel install. His knowledge of this procedure is outstanding and his hourly prices are very reasonable.

 

Thanks for sharing the grip mount slot pictures.

[reconbob]

It is clear from the close up photo of the thread that the barrel is

Not an original or original specification barrel.

 

Bob