Edited by Countryboy77, 26 July 2022 - 07:13 PM.

To Rebarrel or not Us 1928a1
#1
Posted 26 July 2022 - 07:12 PM
#2
Posted 26 July 2022 - 07:34 PM
If you do choose to replace the barrel on your 1928 and "save" the original one, your timing may be fairly good.
APEX Gun Parts just received a shipment of new US made M1928 barrels.
https://www.apexgunp...readed-new.html
They will be restocked in a day or so as we have not properly "received" (checked and counted) them in yet.
BTW, from what I have read, swapping a Thompson barrel is not a simple task.
Richard
#3
Posted 26 July 2022 - 08:31 PM
#4
Posted 26 July 2022 - 08:38 PM
#5
Posted 26 July 2022 - 08:44 PM
Can you tell ys Who made these, and are they chambered to saami specs or slightly oversized per USGI specs as surplus barrels are?
The Ceiner .22 kit I have only fits a USGI barrel with a USGI chamber so I have to ask, but I'd like to grab a couple for spares when I can.
FYI, I have a Richardson wrench and a good vise and clamp (mohawk) that I haven't tried yet.
Also have a forend support device of my own design to pull that away from the barrel while turning.
Having changed three barrels so far, it's really pretty straightforward.....the most time is spent pulling the comp before swapping the barrel, then putting it back on the new barrel, aligning the front sight and pinning that.
My wrench isn't large enough to go over that comp so it's a bit of "back and forth".
Barrels are pre-chambered and should run fine once installed.
If its a new barrel you can yse a cold chisel to tap a witness line on the barrel to match the receiver. After you test-shoot it you can add a little 'p' to the top of the barrel if you want.
The last one I did took under an hour and I was working slowly.
#6
Posted 26 July 2022 - 08:44 PM
Edited by john, 26 July 2022 - 08:53 PM.
#7
Posted 26 July 2022 - 09:04 PM
I have original M1928A1 barrels, finned, threaded for comp.
Stevens square S, MINT-in-cosmoline, in wrapper $395.00.
Bob
#8
Posted 27 July 2022 - 08:41 AM
Not to detract from the issue at hand, but APEXgunparts, do you guys have any other sizeable shipments planned for any thompson parts or accessories in the short term future or have most of the sources of thompson parts and pieces (original and newly made) dried up/unavailable? I am just wondering if the selection that you currently have on the website is as good as it is going to be for a while, or if you guys have anything in the works that I should be checking in every day for? Thanks.
The US made Thompson barrels that APEX sells are manufactured by GMRB.
I supplied the print for the 1928 barrels, it was the original print and GMRB updated it.
Chamber dimensions are the same they used for the M1 Thompson barrels that they manufacture as those have been quite popular for a long time.
Interesting timing on the Thompson parts question.
We recently obtained a quantity of wood furniture and cut receivers.
I believe there are other parts mixed in, but those quantities will be small.
The import of US origin surplus is almost impossible, Pres. Obama put a stop to it.
European brokers have kits, but you can't get permits for them or SMG parts.
Richard
#9
Posted 27 July 2022 - 09:14 AM
#10
Posted 27 July 2022 - 11:48 AM
Has the GMRB Manufactured Barrel been beta tested on a full auto Military TSMG?
Possibly one of my customers can answer that question.
APEX has sold 107 of them to this date.
We have also sold 353 of the M1A1 barrels that GMRB produces for us.
Surely someone fitted one of these 10.5 inch bullet tubes onto an actual SMG!
Richard
#11
Posted 27 July 2022 - 12:29 PM
I have used many Green Mountain barrels over the years on full auto guns
and they are AOK. The only bad thing I can say about them is that they almost
never have them in stock.
The Thompson SMG chamber has a taper has a 0.020" taper per inch where
the standard.45 ACP chamber has a taper of (maybe) 0.003-0.004. In other words
the Thompson chamber is more funnel shaped to assist in feeding.
Over the years some suppliers (Numrich/Gun Parts Corp comes to mind - but
not APEX) have sold Thompson replacement barrels with standard .45 ACP
chambers, and without the radius on the chamber mouth to aid in feeding. A
barrel like this might not feed at all because the cartridge will jam at an angle on feeding
and not make it all the way into the chamber.
The fix is to ream the chamber with a correct Thompson reamer and to machine
the radius on the mouth of the chamber.
The Green Mountain barrels are a little tight - see photos below of what you get when
you ream the chamber with the correct reamer - but not tight enough to cause a
problem.
IMG_1558.JPG 30.18K
41 downloads
IMG_1559.JPG 28.89K
38 downloads
When you rebarrel the gun, it is best to remove the grip mount and screw in the new
barrel hand-tight and test fire. Now you can easily take the barrel on or off without
having to retract the grip mount. If the gun works, then you can unscrew the barrel, fit
the grip mount, re-install and torque on the barrel, and then fit the comp and/or front
sight. If the gun does not work (jams, short recoil, etc.) you have not committed to
anything that cannot easily be undone.
Bob
Edited by reconbob, 27 July 2022 - 01:00 PM.
#12
Posted 27 July 2022 - 01:48 PM
Bob, great idea on the test firing without the fuss if messing with the grip mount. Will try that next time.
I bought one of my '28's with a Numrich barrel on it. The Ceiner kit wouldn't even go into place.
Went to take that barrel off after the chamber "wore out" (excessive headspace) and found the OD was about .094"....,so had to wrap the barrel with about five or six layers of rosin paper to get the wrench tight enough to get it off!
#13
Posted 27 July 2022 - 05:57 PM
Thank you for the response.
Not to detract from the issue at hand, but APEXgunparts, do you guys have any other sizeable shipments planned for any thompson parts or accessories in the short term future or have most of the sources of thompson parts and pieces (original and newly made) dried up/unavailable? I am just wondering if the selection that you currently have on the website is as good as it is going to be for a while, or if you guys have anything in the works that I should be checking in every day for? Thanks.
The US made Thompson barrels that APEX sells are manufactured by GMRB.
I supplied the print for the 1928 barrels, it was the original print and GMRB updated it.
Chamber dimensions are the same they used for the M1 Thompson barrels that they manufacture as those have been quite popular for a long time.
Interesting timing on the Thompson parts question.
We recently obtained a quantity of wood furniture and cut receivers.
I believe there are other parts mixed in, but those quantities will be small.
The import of US origin surplus is almost impossible, Pres. Obama put a stop to it.
European brokers have kits, but you can't get permits for them or SMG parts.
Richard
#14
Posted 28 July 2022 - 07:43 AM
Would it be worth pulling and saving an Original barrel on a Savage 1928 and having a replacement put on for shooting so just in case theres a bad ammo issue or a barrel issue of sone sort for use the original is safe and put away.Or does it not matter once its pulled its not considered original condition.
If your barrel is the original barrel that's been on the gun it's whole life, I'd say no. It's not worth it.
I have an M1 Thompson with it's original barrel as well. I'd like to take the barrel off so I can replace the handguard hanger... But I don't want to pull the original barrel off and not have the front sight line back up again when I tighten back up.
#15
Posted 28 July 2022 - 08:27 AM
Another thing about removing original parts to "save" wear and tear on them is that too often the owner passes, or the gun otherwise changes hands with the original parts missing. The gun and its parts are never reunited.
I have an M1928A1 with its perfect original barrel. Better to shoot it as is than to modify the gun. I'm aware of the remote possibility of a bulged barrel from a squib load. My plan is to investigate if a round does not feel right.
In about a billion years my gun will be a very dim memory. Better to enjoy it now.
#16
Posted 28 July 2022 - 10:16 AM
I have been lucky to own 4 Thompsons one was a Colt. I shot all of them a lot. I stopped counting after 15,000 rounds. All rounds were hand loaded by me. I never bought a box of factory ammo. Most of my shooting was dome outside using cast 230 grain round nose. I would shoot clad bullets inside lot less smoke. All barrels looked the same when I sold the Thompsons as they were when I purchased the. I used the same load for over 20 years. Load was 5.5 Winchester 231 with a slight taper crimp in die station 4. Let the barrel on shoot gun as is. Just my 2 cents.
C K
#17
Posted 28 July 2022 - 11:24 AM
If you remove a barrel - for whatever reason - when you go to
put it back on, if you torque it on tight it will go on a little farther
than before and the sight will be slightly too far to the left as you
sight the gun.
BUT - sometimes you can get away with it. If the barrel was previously
torqued on really tight, the barrel may get tight enough when the
sight lines up the second time. You never know until you try. What
you want is you don't want to be able to unscrew the barrel by hand.
If it is tight enough that you can't do that, you should be OK.
Bob
#18
Posted 28 July 2022 - 05:08 PM
Thanks for answering that question, Bob