MGC Thompson Revisited

Post by ricks

I just bought an MGC Thompson off of eBay, and it appears to be a display model: flat extractor w/ screw, blocked barrel. I hope to convert it ASAP. Any thoughts for the good of the order?

As near as I can tell, the bolt has not been cut. Is it good for anything (other than a boat anchor or a paperweight)?

I currently have a Marushin MP40, which I built from a kit from www.wwiiguns.com, an MGC Ingram M11 (needs suppressor), this Tommy, & a modest airsoft collection.
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Rick

Post by ljerr2

If the bolt face is at an angle, then it has been cut.
Most of the Tommy's for sale have blocked barrels, but they are still cap firing models. I'm not sure what you have without any pics of the chamber area and bolt. If you want to post a few pics, I'm sure we can tell you what you have and what you will need.

Post by ricks

Here are some pics - sorry about the quality on some. Thanks in advance for your help.







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Rick

Post by Mark

Hi Rick,

It appear that you ended up with the second early MGC Thompson that I have seen that was imported. Although, you still have the "Display only" version (No chamber and a non-functional extractor) The conversion to the firing version isn't that difficult/expensive it just depends on what you envision doing with the MGC (or any other modelgun) that you may have. If you just like the looks of the Thompson and it just is a "wall hanger" to you I guess it's fine the way it is now. But, if you intend on "firing it" the parts, knowledge, cartridges as well as the caps to fire it are available from the sources on this forum.
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Wanted to buy: MGC Sten MK3....trades?(still)

MGC MP40 Marushin MP40 Nakata MP40 TRC MP40

Modelgun manufacturers, past and present:CMC,CAW,Hudson,HWS,LS,MGC(R.I.P. 1960's~2007) Marushin,Marui,Kokusai,Shoei,Tanaka and Western Arms

Post by shazhib

Rick,

Is a chamber been stuffed with something?
Needless to say, you need to eliminate the stuffing if you want to fire it (also need a chamber and det-pin). As mark mentioned, it really depends on how do you want your Thompson be

Post by ricks

The chamber appears to have a metal plug that is held in place by the set screw that comes up from underneath. I do want to remove it and make this a firing model, unless for some reason this will destroy its value.
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Rick

Post by ljerr2

Ricks,
I don't know if there is any more value in it the way it is. You could probably convert it to firing and save the parts you remove so it could be restored to its current condition if you decided to do so later.
Sounds like you should have a pretty straight forward conversion, especially if the chamber "plug" is held in place with the screw from the bottom. You'll probably need to buy a chamber, bolt assembly, and maybe the rubber bolt bumper (may not be there now). Looks like you may need to do a little material removal on the upper receiver to fit the new style bolt (this is internal, so nothing noticeable from the exterior). You might be cautious in separating the upper receiver from the lower receiver when you disassemble the gun. The reason I say this is that they are tiny screws and I think some of the "display" models had the screws had threadlocker applied to them.
J

Post by ricks

Thanks for the heads-up about the threadlocker. Would it be safe to apply heat first? I'm reluctant to use a torch, but I have a heat gun and a soldering gun. I've seen others hold the tip of a soldering iron on a screw to loosen threadlocker. Is this recommended? Also, I'm not familiar with the rubber bumper - what is it? Further, if I can't un-block the barrel, will the gun still fire? (The third photo above gives a good view of the blocked chamber.)
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Rick

Post by Claymore

The rubber bumper is at the rear of the gun and stops the bolt smashing into the rear of the receiver, as long as you can unblock the chamber then a blocked barrel is no problem, most thompsons have a blocked barrel its no problem for PFC.

Post by ljerr2

Claymore is right about the bumper. If the bolt charging knob will go all the way to the back of the slide and contact the upper receiver, then the rubber is not there - you will feel the cushion if it is there and the bolt knob should stop short of contacting the back of the receiver. Another possible way to tell is if the spring guide pin sticks out of the rear receiver more than about 1/4", then the bumper is probably not there.
As far as removing the plugged chamber, I wouldn't anticipate this to be too difficult, as the model was not made with it and it was installed after manufacture. There may be a pin from the bottom in addition to the set screw that holds the plug in place. You may have to remove this.
As far as the screws, I'd pull the rearmost allen head screw at the back of the receiver first. Even if it has threadlocker, it will be easy enough to break loose due to the size of the fastener. If it is clean, no worries. If it has threadlocker, you may wish to apply heat via the soldering tip to the two smaller front receiver screws. However, you might be ok without heat and just being super careful to make sure your screwdriver is exactly perpendicular to the fastener and exert sufficient downward pressure to avoid the tool blade from slipping out of the fastener slot.

Post by ricks

The project continues...
The "chamber" is now out; the set screw from the bottom of the chamber came out easily (no threadlocker - phew!), as did the receiver screws (which haad allen/hex heads). Since this model was display-only the rubber buffer/bumper is not there. If anyone is interested, I can post pics of the chamber "plug," etc.
Now, if I can only track down the PFC parts...

Again, thanks for the input. You guys rock!
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Rick

Post by ljerr2

Congratulations on your progress. I hadn't noticed from your pics before, but this appears to be an open-barrel model. Now that the plug is out - you should be able to tell if it vents through the front. If it does, this model just became worth a lot more money in my eyes! Get the PFC parts and have fun!

Post by ricks

The only thing in the barrel is the obligatory vertical sheet metal "nongun" insert. Yahoo!
The "plug" looks like a piece of steel bar machined so the set screw would retain it.
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Rick