Early Front Vent Thompson Info...

Post by Doc

Mods please feel free to pop this into another section if you feel its more appropriate .

Just a few images of the Early MGC Thompson parts , (the front vent version) . As you can see the early chambers did have that little locating lug at the bottom and appear cast made rather than machined .
you can also see the quite open slots in the back of the chamber to allow gasses out of the front early models.
Early type bolt is shown too , in quite remarkable condition considering its age , I estimate this (as well as the rest of the gun) had fired about a half dozen rounds (if that) before being stored away .
The extractor screw had a thin layer of glue to secure it ..that I presume was pasted on at the factory all those years ago .








the rest of the gun is pretty much like the others but I figured these details may interest someone .

DOC
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We need guns...lots of guns....

.... well anything mechanical that can kill people is interesting ...

Post by Mark

Thanks for the pictures of an un molested, paper cap setup. With all of the CP modified Thompson's around it's interesting to see the paper cap bits even if the gun has been converted. Most of the converters as you know, use the paper cap chamber as it has the gas escape holes for the open barrel. I would suppose that the early bolt might work even with the somewhat "crude" leaf spring extractor assy.
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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

Does anyone know when MGC started blocking the barrels up on the old type 1921 Thompson models please?
One of mine appears to be date stamped 1978, the gun has the old type receiver arrangement, the bolt and det. chamber have been replaced by later c.p. types but the barrel appears blocked.
The blockage is open down to (very approximately) 1" to 1 1/2" behind the det chamber.
Any ideas what MGC used to plug the barrel? Can it be removed easily?

Cerwyn
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Hobby collector of mainly WW2 era uniforms, headgear, field equipment and replica weapons.

Post by Doc

Well the regulations came in concerning MGCs MP40s in 1977 so it would be reasonable to presume MGC had to block the barrels on their Thompsons and M16s at this date.

As with early open barrelled M16s This Thompson is undated.

as for the blockage ...Id expect it to be harder than the surrounding material to prevent /deter drilling and most likely it will have been added during the casting of the Zinc


DOC
_________________
We need guns...lots of guns....

.... well anything mechanical that can kill people is interesting ...

Thanks DOC, looks I missed out by a year then, pity that.

If the plug is going to prevent drilling it'd be risky trying I suppose. Wouldn't want to have a drill skid off the plug and out the side of the receiver!
It'd be a challenge to support a drill that long too as it'd need to enter through the muzzle so the chances of skidding would be even greater.

Thanks for the info!

Cerwyn
_________________
Hobby collector of mainly WW2 era uniforms, headgear, field equipment and replica weapons.

Post by 8ace

Guys,

Is the locating lug on the outside of the chamber necessary for it to fit and stay in the receiver

8ace

Post by Doc

Nope. it just helps line up the openings in the chamber with the spaces in the gun.
i.e doesnt open directly into the metal bar that is there to prevent projectiles going down the barrel.

DOC
_________________
We need guns...lots of guns....

.... well anything mechanical that can kill people is interesting ...

Post by ricks

cerwyn wrote:

Does anyone know when MGC started blocking the barrels up on the old type 1921 Thompson models please?
One of mine appears to be date stamped 1978, the gun has the old type receiver arrangement, the bolt and det. chamber have been replaced by later c.p. types but the barrel appears blocked.
The blockage is open down to (very approximately) 1" to 1 1/2" behind the det chamber.
Any ideas what MGC used to plug the barrel? Can it be removed easily?
Cerwyn

Mine was blocked with a piece of steel bar that fit the barrel where the chamber/detonator goes. After using penetrating oil on the set screw, I backed it out & the "plug" fell right out.

Post by Doc

I believe Cerwyn is talking about the blockage behind the chamber on the closed barrel versions and not the blocked chamber types as exported to the US .

DOC
_________________
We need guns...lots of guns....

.... well anything mechanical that can kill people is interesting ...

Yes, the plug I'm talking about is located behind the detonator chamber.

One thing though, this particular Thompson had been converted to fire c.p. rounds before I bought it. The chamber and bolt had been replaced simply by fitting new types, nothing else.
Unfortunately, the new style chamber doesn't have the lug along it's length and consequently fell out of the gun when I attempted to fire it first time. The set screw simply isn't long enough to secure it in place without that lug sitting in the groove.
There was a lengthy discussion about this at the time and Reemos' suggestion of inserting a piece of copper packing stapel into the slot worked a treat. The set screw now has something to push against and it holds the chamber firmly in place.

Cerwyn
_________________
Hobby collector of mainly WW2 era uniforms, headgear, field equipment and replica weapons.

Post by ljerr2

Cerwyn,

What about just using the chamber set screw from a newer version Tommy? Shouldn't it be a little longer and be the same thread pitch, etc? Sounds like a more permanent fix than the staple?

Post by Doc

M4 x about 13mm of thread will do you

screwfix will do some M4 x 16 you could cut down or you could get ripped at fleabay ....

http://cgi.ebay.co.uk/STAINLESS-COUNTERSUNK-ALLEN-BOLTS-M4-X-16-20PK-FREE-P-P_W0QQitemZ150172003993QQihZ005QQcategoryZ41500QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

DOC
_________________
We need guns...lots of guns....

.... well anything mechanical that can kill people is interesting ...

Post by ljerr2

Like Doc said, you could get a screw to size somewhere or cut one down. There's also the ability to have one of our friends in Japan get us the factory original replacement screw - right color and right size - should be no swearing involved!

Funnily enough I already tried the screw from my other, later, Thompson and that ain't long enough either!

I take your point though, a longer screw should work perfectly well

Cerwyn
_________________
Hobby collector of mainly WW2 era uniforms, headgear, field equipment and replica weapons.