Front End Of Blank Firing Barrel

[reconbob]

Here is the front end of the blank barrel that had the ring in front

of the chamber. We don't know what the condition of the bore was

before the barrel was "blanked", but there is no noticeable damage

or erosion to the barrel just rear of the blank adaptor, or to the

blank adaptor itself. The orfice in the adaptor measures 0.187" and

I figure it was made with a 3/16 drill, so there has been no wear.

There is some carbon build-up on the rear face of the adaptor and

the rear threads are also full of crud.

I had expected to see wear and burnt out rifling like you see with

Garands that fired a lot of blanks, but for whatever reason it didn't

happen. Just goes to show you never know.

A board member is sending me another Thompson blanked barrel

that he says has three rings in the bore so we can take a look at that

one too.

 

Bob

 

http://i51.photobucket.com/albums/f392/reconbob/IMG_1623.jpg

 

http://i51.photobucket.com/albums/f392/reconbob/IMG_1624.jpg

[EM1/SS]

Any pictures of the ring?

[reconbob]

Here is the thread with the photos of the ring - I started a new

topic since the old one started to ramble...

 

http://www.machinegunboards.com/forums/ind...showtopic=12528

 

Bob

[EM1/SS]

Thanks, there's a lot of good info there.

[Blanksguy]

No errosion nor "ring" at the muzzle is probably due to less pressure as the burning powder-pressure would be less as it reaches this point (?). The higher-presure as the crimped-blank-cartridge starts to open acts as a very short duration "blow-torch"........IE: The initial firing and opening of the crimped case during firing of those Swanson-Blanks (?).

 

Would be nice to know if the barrels in question were original USGI (seem to have better heat-treatment (??)......or recent West-Hurley manufactured barrels (?).

 

Also, was this the barrel that had the "ring" just forward of the chamber in your earlier thread (?)...........might be nice to keep both threads together for "reference" on firing Blanks in Thompsons..........and maybe a "board-moderator" could attach this thread to the other if you would like (?).

 

Regards, RichardS in MI.

US Army, Retired

Blanksguy2001@chartermi.net

[wwiifirearms]

The barrel at the start of this thread showing the BFA is the same as the one with the ring near the chamber ( came off my gun). This was an original GI m1a1 barrel, even had British proofs.

-wwiifirearms

[reconbob]

Sorry, I thought the other thread went adrift so its my fault there's

two threads here. Maybe our fearless leader can select the relevant

posts and pull it together.

As was just mentioned this was/is a GI barrel.

I received the barrel from Jim C that has two bulges and a ring.

The bulges are from bullets getting stuck in the bore and the barrel

has the ring ahead of the chamber from blanks but not as bad as this

first one. When I get a chance I'll section it and post the photos.

I just converted an M1 pattern Kahr semi to a legal non-SBR blank

firing only rifle with a 10.5" barrel. The 16" barrel I took off also had

the beginnings of a ring ahead of the chamber from shooting "1000's"

of blanks. The guy said he used Swanson blanks, but I don't know if

they were the only blanks he used or not.

When I test fire the blank firing guns I was using an open side down

thick cardboard drum with a small hole that I put the muzzle thru to

act as a muffler for the sound. The drum got wet so today I switched to

a 30 gallon plastic trash can with a small hole in the end and the 5th

shot of a Swanson blank blew it to pieces.

 

Bob