Tommy Gun Pierced Primers!!!!

[EMC45]

A buddy of mine just got a Thompson (Kahr) Tommy Gun and shot it a bunch the other day and brought all the brass to me. Well upon unloading the MaoMart bag I noticed the primers and they don't look good at all. You can actually see daylight through a few of the pockets. He sent this image to Kahr and they said "perfectly normal. We have boxes of spent cases like this here" I don't think this is normal AT ALL!!!!! What do you guys think? The left case was fired from a Springfield 1911A1 GI Spec.

[Storydude]

I think when your friend gets a facefull of hot gas, Kahr will be in a lawsuit.

[oneokie]

Firing pin is protruding too much. .055"-.060" is standard. Your friend should contact Kahr again and see if they will tell him what the fp protrusion spec is.

[EMC45]

I also told him the FP was out too far. He said the bolt was very dirty. I presume from hot gases. I also told him to save the Email traffic so when he did get a faceful of hot gases he could have a leg to stand on. I also told him to not fire the gun anymore. He did say Kahr offered to ship the gun back on their dime for them to look at. That sounds a little off from"perfectly normal" huh?

[Hardcast416taylor]

Okay, stop for a moment and ask yourself how many other firearms you have either seen do this action or you have heard of doing this? This is not right! If the firing pin must stick out so far to pierce the primer cup that badly just to fire the cartridge IT IS OUT OF SPEC.!!! I`ve seen worn war time full auto Thompson`s not do this to primers, and this is a fairly NEW semi-auto version?Robert

[shotman]

It also wont take very long to erode around the firing pin

[EMC45]

I told him about the hot gases and erosion as well.

[klcarroll]

Wow!! .....That's a a real "World Class" primer hit!!!

....Even my 1976 vintage MAC-10 doesn't crush them like that!!!

Kent

[TNsailorman]

If Kahr offered to take a look at it on their dime, I would send it back to them and let them check it out. I don't like the looks of those primers either and I would bet that they will not either. I too think the firing pin is a bit long. I would fire maybe 6 more cartridges in it and send it back without cleaning to let them fully see the problem. Send along a couple of the fired cases also. I would take pictures of the bolt face and the spent cartridges and keep copies of the correspondance also, just in case. Comparing a 1911 to a Thompson, though, is comparing apples and oranges. The 1911 fires from a closed bolt captured firing pin and the Thompson from a open bolt(basically a slam fire). At least that is my memory from the good ol days with the Navy & Marines when they were still issued. Its been a long time though and I have slept at least twice since then. James

[klcarroll]

Well, .........The comparison between the Kahr and a 1911, is actually pretty valid.

The Kahr (and all currently offered Thompson look-a-likes) fires from a closed bolt, and employs a striker.

Ever since the debacle that followed the release of the first semi-auto MACs, the BATF has had an allergic reaction to anything that fires from an open bolt!

Kent

[mstarling]

I believe the Kahr (just like the West Hurley Auto Ordnance) semi Thompson is closed bolt. My Auto Ordnance 1927A1 semi does not leave primers looking like that at all.

Sending it back to them sounds like the right thing to do.

[EMC45]

It is indeed a closed bolt gun. The photo above was sent directly to Kahr. They are the ones that said it was "normal". I know it is not normal AT ALL!!! They said they have boxes of spent brass that looked just like this and no worries.

[rockrat]

My AO 1927A1 doesn't do that to primers either. Another firing pin would probably solve your difficulties, assuming the protrusion is not identical.

[revolver junkie]

i recenty shot a semi tommy gun and the primerslooked fine o me sound like hes god a out of spec gun

[JW6108]

They said they have boxes of spent brass that looked just like this and no worries.

Brush off, pure and simple.

[klcarroll]

ANY time you have pierced primers and gas blowing back into the action (...and the region of your face) it is a BAD thing!!

.....As I mentioned before, even my F/A MAC-10 with it's "48 caliber" chamber doesn't do THAT to the primers!!!!

Kent

[Lloyd Smale]

my buddy has a rifle and the pistol version and they both did it. He cured it by switching to cci primers. there cups are a bit harder and that seems to take care of it.