1928 barrel removal

[jake]

I need advice on changing the barrel of a 1928 Thompson.  How do I do it?

Edited June 23, 2025 by jake

[Got Uzi]

With the proper tools. You don’t want to try and improvise it or bad things can happen. 

[TD.]

Jake,

I know 3 business dealers in different States that have the experience necessary to properly remove and replace a Thompson barrel. One just posted above. Let us know in what State you reside.

[jake]

Thank you for helping me.  I am in alabama. 

Edited June 24, 2025 by jake

[TD.]

Someone closer may chime in that has the experience to change a barrel. If not, I would reach out to Got Uzi, above, in Uhrichsville, Ohio. He does excellent work and his prices are very reasonable. If your not interested in shipping, Google your location to Urichsville, Ohio and see how long a drive you have.  Send Got Uzi or John a Private Message with your contact information and I am sure he will reply. Just click on his name and you will find the Message button.

What type of Thompson do you have? Is the reason for a barrel change a bulge?

[jake]

It’s a 1928a1.  It has an M1 barrel on it and I want to put a barrel w a compensator on it 

[TD.]

I am definitely not a gunsmith but the job you have in mind is more than just changing a barrel. I would guess you also want a compensator attached and pinned. I would also make sure you have a milled grip mount. And make sure whoever you hire can do the complete job.

Don't hesitate to ask additional questions and visit the Thompson forum often.

Good luck and let us know how it turns out.

[jake]

It’s a 1928a1.  It has an M1 barrel on it and I want to put a barrel w a compensator on it 

[jake]

I have a barrel for it with a compensator.   

[TD.]

If the compensator is already attached to the 1928 barrel, it may line up perfectly when installed. Or not. If not, you need someone that can reposition the compensator properly on the barrel. For those that routinely do this work, it is not a big deal. And there is little worry about damaging that very expensive registered receiver.

[Rekraps]

15 hours ago, jake said:

Thank you for helping me.  I am in alabama. 

Jake, somewhere on this Forum is a member who sells custom made barrel removal wrenches. Might be worth investigating. 

[Mattg203]

I’ve been wanting to change the barrel on my C&R AOC 1928a1. I have spare nos barrels already. What would the average cost be to do this? Thanks 

[reconbob]

   I looked and here is a sample worksheet for barrel work -

 

M1A1 (original G.I. full auto)

 

Remove barrel, remove grip mount, clean barrel thread and grip mount

slot, check fit of new barrel, fit grip mount and barrel, remove front sight

from old barrel, old sight is too loose on new barrel and cannot be used,

fit new G.I front sight - 50 min

 

Assemble. test fire, disassemble - 14 min

 

Drill and pin front sight (requires set up in milling machine) 22 min

Final assembly - 4 min

 

Total minutes 90 @ $125/hr = $180

 

This is just a typical job with no problems or surprises. 

 

Bob

 

 

[john]

That sounds about right. I've done it with and without the use of a mill. It's not tough with the right tools and if things come apart pretty easily. The mill will guarantee the front sight is absolutely straight up and down.

Done mine a couple times without and it's not tough but takes extra time to get that sight close.

Lots of hand work and fussing around, all  just time consuming.

I'm in Minnesota and not in business, just working on my own guns......I don't do thus as a business because, well.....no insurance in case someone's baby is damaged, ya know?

I know there are several good folks in biz who probably are way more proficient than I am too, probably several collector/shooters like me also who are capable. Receiver vise and wrench might set you back 3 c-notes or more but last forever....and there are a couple great  videos that'll take one through the process step by step too.

Good luck!

John

[Sig]

On 6/26/2025 at 12:44 PM, reconbob said:

   I looked and here is a sample worksheet for barrel work -

 

M1A1 (original G.I. full auto)

 

Remove barrel, remove grip mount, clean barrel thread and grip mount

slot, check fit of new barrel, fit grip mount and barrel, remove front sight

from old barrel, old sight is too loose on new barrel and cannot be used,

fit new G.I front sight - 50 min

 

Assemble. test fire, disassemble - 14 min

 

Drill and pin front sight (requires set up in milling machine) 22 min

Final assembly - 4 min

 

Total minutes 90 @ $125/hr = $180

 

This is just a typical job with no problems or surprises. 

 

Bob

 

 

Money WELL spent to do it correctly.  

On 6/24/2025 at 11:30 AM, TD. said:

If the compensator is already attached to the 1928 barrel, it may line up perfectly when installed. Or not. If not, you need someone that can reposition the compensator properly on the barrel. For those that routinely do this work, it is not a big deal. And there is little worry about damaging that very expensive registered receiver.

Totally agree with Tom.  While there might be available barrel changing tools, when installing another barrel, to get the compensator to correctly line up, almost assuredly will require a machine shop, preferably one with experience.  A different barrel with an already pinned on compensator, more likely will not line up perfectly, thus the need to remove the pin, line up the compensator, drill and pin it in the correct lined up position.  

[Colt Chopper]

On 6/26/2025 at 12:44 PM, reconbob said:

   I looked and here is a sample worksheet for barrel work -

 

M1A1 (original G.I. full auto)

 

Remove barrel, remove grip mount, clean barrel thread and grip mount

slot, check fit of new barrel, fit grip mount and barrel, remove front sight

from old barrel, old sight is too loose on new barrel and cannot be used,

fit new G.I front sight - 50 min

 

Assemble. test fire, disassemble - 14 min

 

Drill and pin front sight (requires set up in milling machine) 22 min

Final assembly - 4 min

 

Total minutes 90 @ $125/hr = $180

 

This is just a typical job with no problems or surprises. 

 

Bob

 

 

Sounds like one heck of a bargain to me if you need a barrel replaced and done right. Less than $200 to save yourself the aggravation, that's a no-brainer.

[reconbob]

        Things that can add time, and therefore expense -

        -  new mfg. barrel - many will not screw into the receiver without fitting

        - correcting .45 ACP chamber on new mfg. barrel. Most new barrels have the standard

           .45 ACP chamber which is more straight-walled than a Thompson chamber and cartridges

           will jam on feeding unless corrected.

         - barrel does not get loose. Maybe 1/3 of the time once the barrel "breaks" free, it cannot be

            unscrewed by hand and has to be wrenched off the whole way. This can only be done a little

            at a time because the grip mount hits the jaws holding the barrel after only a short amount

            of turning.

         - compensator does not get loose. As above, if it has to be wrenched off all the way it adds

            time. Also, if it has to be wrenched off, it will not screw back on unless the threads in the comp

            or on the barrel, or both, are dressed with a tap or die.

        Bob

       

[bug]

Yes, the devil is in the details...

[Countryboy77]

For what recon bob quoted tgats NOTHING compared to the price of ypur transferrable you spend far more on ammo! I would say pay a pro who has tge tools to do it right and the practice actually doing it ,but also being able to clock it right if it doesnt line up.Its just as much to buy the special tools and you still gotta hope all goes well.Considering tge value of tgr investment its a no brainer ,make a reservation and a road trip,or ship it out and it will come back like you want.

[Doug Quaid]

I like to tinker with stuff

but I pick my battles.  this would be a job that I would farm out

[Mattg203]

I am also in search of a WWII original M1928A1 smooth barrel with compensator with parkerized finished to match my late model AOC Thompson. Mine has the smooth barrel on it now (it’s a WWII Savage replacement) but would like to replace it at some point because I think I’m shooting it way too much. Some 3000 rds in one year. Got it in July of last year. 
 

What’s the life on one of these barrels btw? 

[Got Uzi]

The odds of “wearing out” a barrel at 3,000 rds a year isn’t an issue. Most barrel issues anymore come from squibs/bulges or damage caused by someone doing something stupid (dropping it or whatnot)

Thompson barrel could last up to 50k-75k+ rounds or more. Im shooting my Savage M1A1 that has the original barrel in it that was converted to be a blank firing (threaded the bore at the muzzle) and it still shoots amazing. 

[Colt Chopper]

Wrong board

Edited July 4, 2025 by Colt Chopper

[jake]

I’ve sent said gun to Got Uzi

[jake]

On 6/23/2025 at 11:45 PM, TD. said:

I am definitely not a gunsmith but the job you have in mind is more than just changing a barrel. I would guess you also want a compensator attached and pinned. I would also make sure you have a milled grip mount. And make sure whoever you hire can do the complete job.

Don't hesitate to ask additional questions and visit the Thompson forum often.

Good luck and let us know how it turns out.

The barrel change is complete and the weapon is back home.  Gotuzi did the work.  It looks good and fires even better.