West Hurley magazine problem

[OralOperator]

Hello, I am new to the forum, but Ive been reading a lot and learning a ton already.

 

I recently acquired two WH WWII commemorative edition Thompsons. Im slowly getting them running well by replacing everything with GI parts. However, I currently have to hold the stick magazines up in place a small amount in order for the guns to run well. If I dont hold the mag in place, the bullet gets jammed into the feed ramp. Drum magazines run perfectly.

 

Is this a common problem? Is there an easy fix?

 

Ive ordered a parts kit off of gun broker, so hopefully a GI lower receiver will solve the issue, but that wont be here for a few days, and its expensive too, so Id rather not order another one if I didnt have to.

[ron_brock]

Welcome to the board!!

 

Is the hole on your mag round or oval? The oval mags are modified to fit a semi auto. Just want to confirm that its not something super easy first

 

Ron

[Ryo]

That was what I was wondering. The circle holes are for the SMG. The oval ones are for Semi Auto. Possibly you received modified magazines.

[Sandman1957]

Welcome to the Forum, you found the right place for straight forward Thompson knowledge!! Once the parts kit comes in, try the lower on both guns. If it works it solves your problem. Then you should only need a second complete lower. That would be better than a complete 2d parts kit.

 

Look at all your mags. Any that have ovals will not work in Full auto as stated above. When you buy mags always check first if you are buying them at a gun shows or in a physical store.

 

Also recommend you filling in a little more info on your profile. Look at mine and you will see I am in Virginia. If folks can see where you are, some may reach out to you if you are near them and give you assistance. You don't need to be overly specific, but most folks here are always trying to assist others. I have done it on many occasions.

 

 

Enjoy!

Sandman1957

Edited March 4, 2021 by Sandman1957

[deerslayer]

Usually the West Hurley's need a little more milling in the feed ramp area and correct GI magazine catches. Plus you have to make sure your feed lips on the magazines aren't squished. Chambers will be tight. You don't need a new GI lower.

[OralOperator]

Thanks guys!

 

All of the mags I have are circle holes, not oval. I will definitely swap out the lowers when my new one comes in. Hopefully that solves the problem.

 

Sandman, I will get my profile filled out a bit more, thanks for the tip!

 

Deerslayer, I understand that someone with a machine shop may be able to modify a WH lower to work better, but I just don't have that ability at the moment. Down the road it's something I could have done by someone more capable, but in the short term I need something a little easier.

[TD.]

OralOperator,

Welcome to the Thompson forum! The West Hurley Thompson guns have been discussed at length over the years. Board member deerslayer makes an excellent point in his above post. You may not need a USGI frame. But if you decide to install a GI frame, go slow and make sure the rails are lubricated. There are manufacturing tolerances in all things Thompson. Auto-Ordnance in West Hurley, New York took these tolerances to a new level It is not uncommon to find GI frames that will not fit on a West Hurley Thompson. Or a Colt's for that matter. If it is easy on and easy off, you are good to go. If it starts getting tight, I would stop. Again, use plenty of lubrication. You do not want to force anything.

 

One other thing. Make sure the buffer pilots in your two West Hurley Thompsons are marked with the letter "S" denoting Savage Arms. Unmarked buffer pilots are usually two-piece and can separate while firing. You also want to use polyurethane buffer discs. Board member PK makes the best discs in my opinion - under $10 apiece. In addition, your problem could be nothing more than a cast West Hurley magazine catch (does it have a purplish color?). A properly fitted GI magazine catch can solve many problems. Shown below is a link to a story I wrote about West Hurley Thompson parts in 2011.

 

https://www.smallarmsreview.com/display.article.cfm?idarticles=224

[OralOperator]

OralOperator,

Welcome to the Thompson forum! The West Hurley Thompson guns have been discussed at length over the years. Board member deerslayer makes an excellent point in his above post. You may not need a USGI frame. But if you decide to install a GI frame, go slow and make sure the rails are lubricated. There are manufacturing tolerances in all things Thompson. Auto-Ordnance in West Hurley, New York took these tolerances to a new level It is not uncommon to find GI frames that will not fit on a West Hurley Thompson. Or a Colt's for that matter. If it is easy on and easy off, you are good to go. If it starts getting tight, I would stop. Again, use plenty of lubrication. You do not want to force anything.

 

One other thing. Make sure the buffer pilots in your two West Hurley Thompsons are marked with the letter "S" denoting Savage Arms. Unmarked buffer pilots are usually two-piece and can separate while firing. You also want to use polyurethane buffer discs. Board member PK makes the best discs in my opinion - under $10 apiece. In addition, your problem could be nothing more than a cast West Hurley magazine catch (does it have a purplish color?). A properly fitted GI magazine catch can solve many problems. Shown below is a link to a story I wrote about West Hurley Thompson parts in 2011.

 

https://www.smallarmsreview.com/display.article.cfm?idarticles=224

 

I already read your article, it was very informative! Thanks for your advice, I will take it really easy when trying to switch out the lowers. I am having a different issue with one of the lowers not functioning properly. I know it's the lower because I switched lowers between the two guns and the problem follows the lower. It will do like a 3 round burst or fire one or two rounds at a time, but won't reliably fire full auto. I am going to completely disassemble the lower tonight and see if maybe it just needs a good cleaning and lubrication or if I need to start swapping parts in it as well.

 

I ordered new buffers (from Sarco I believe) already after reading your article earlier in the week, and have already installed the polyurethane buffer disks in both of the guns. I also ordered new magazine catches for both guns, I am just still waiting on them to arrive.

 

Thanks for your help.

[Ryo]

@TD: I didn't know you made that article. I read that article many times. Thanks for that one. (FYI: Formatting in Chrome looks cut off. Hit Ctrl-A to highlight everything and you can see the hidden words)

 

FYI:

PK still sells the buffer for $7.50. You just have to mail him a check for it. I'm still waiting for mine to come in, I sent my check last week.

[Mike Hammer]

I had the EXACT same problem with my first West Hurley. It's the magazine catch, I would bet the house on it. Drums work fine right? That's because the drum mag rails are holding the Drum in the correct position. Either swap out the current mag catch with a GI catch or you could use a slight dab of something like Weld-On to make the tip of the mag catch where it holds the mag in the mag housing fit tighter into the gun, about 1/32 or 1/16 of an inch higher or longer might do it. When you look at it you'll understand what I mean. It's really a pretty simple fix. Don't mess with the feed ramp until you try something like this. Look at your mag well and see how the stub of the mag catch pokes through to be able to hold the stick mag on.

 

MH

[OralOperator]

Thanks Mike! Hopefully my GI mag catches show up soon so I can swap it out and see if that fixes it.

[OralOperator]

I changed out the magazine catches this morning and that completely solved the issue! Thanks guys.

[Moonrockamps]

Where did you source the GI mag catch? I read the SAR article this morning. Excellent. Thanks,

Bruce

[Mike Hammer]

I changed out the magazine catches this morning and that completely solved the issue! Thanks guys.

Glad it was a relatively simple fix as I suspected. Now what are you going to do with that parts set now that the gun is working fine? They are only going up in price so you can probably turn a profit on it later if you don’t need the parts.

[StrangeRanger]

Sources for mag catches

 

https://www.apexgunparts.com/machine-guns/sub-machine-guns/thompson-45-acp.html

https://tommyguncollectibles.com/m1-lower-internals/

Edited March 10, 2021 by StrangeRanger

[Moonrockamps]

Thank you for the links. I wound up purchasing a Pilot and Mag Catch from RTGParts. Based on the article, I will shop for an Actuator next.

[OralOperator]

The parts kit showed up today. I swapped out the lower receiver on the one Ive had cycling issues with and its 100% fixed. Both guns are running perfectly now! Thanks again guys!