Pierced primers in 1911

[RSVP2RIP]

Is high pressure the only culprit for a pierced primer? Specifically the gun was a Colt MkIV in 9x23. The primers look like a cookie cutter made a perfect circle in the primer with no other signs of high pressure like flattened primers or case marks. I only realized what was going on when The cartriges weren't going off and I picked up some brass. 4 were pierced and the ones after were barley dented. Dissasembling the gun showed 2 of the brass disks from the primers were in the firing pin channel causing the light strikes. The ammo was factory Winchester Silvertip. Would a lighter firing pin or heavier firing pin spring help?

 

[rcmodel]

Could be a couple of things.
1. The firing pin tip has already been eroded by leaking primers to the point it is now rough and/or sharp on the rounded end.

2. The hole in the slide is larger then the firing pin, allowing the primer to flow back around it. The FP should fit the hole in the slide real close to exactly on a 9x23.

3. Soft primers, like Federals can contribute to it too. If you are shooting reloads, change to CCI primers as they are harder then most other brands.

A weak firing pin spring, hammer spring, or recoil spring could contribute to it too I suppose.

rc

 

[HisSoldier]

How about a 9MM firing pin in by mistake? If the firing pin looks like a normal firing pin, that just fits the hole, we have a mystery. Tuner?

 

[RSVP2RIP]

Looking at the firing pin further, it appears bent slightly and does not pass though the FP channel freely. How could it bend? Too much extractor or just trying to eject while in a primer? It fits extremly close in the firing pin hole and is nice and round on the point.

 

[RSVP2RIP]

bump

 

[Deanimator]

Replace the firing pin and spring with known good components. Unless you previously had the firing pin out (most people don't for a while), you wouldn't know WHAT it looked like. It could have come that way from the factory.

 

[BullfrogKen]

The ammo was factory Winchester Silvertip.

When I shoot current factory Silvertip in my 9x23 I've seen early signs of that happening, too. Mine don't quite pierce like what you decribed, but they do flake off a bit. Once in a while I had the primer material flake off and clog up the firing pin hole. My top end was a complete build by Jim Garthwaite using a Caspian slide.


Like rcmodel suggests, the firing pin needs to very closely fit the hole when you're shooting 9x23. That round is really high pressure, and the primer is the weak link in this particular cartridge. If there is any space for the primer to expand back between the firing pin and the firing pin hole, with a softer material primer it will flow back.


I really don't know what Winchester did, or what they're using now to assemble 9x23 Silvertip rounds. But the primers are most definitely too soft with some of the boxes I bought about 4 years ago. When I load 9x23 at home, I use small rifle primers. Period. The challenge is if your mainspring is a little light, or the assembly of your 1911 makes for a light hammer strike, it won't have enough force to set the primer off. Go to a softer primer, and the high pressure of the 9x23 will tear it up.

Some of those 9x23 Colts weren't made quite the way they should have been to shoot the 9x23 properly. The round was still in its early stages of development, and Colt didn't do too much besides re-spring 38 Supers and drill the chamber to 9x23 dimensions for most of what left the factory. The tolerances on the fit of certain parts, like the firing pin, are a lot less forgiving of a sloppy fit.


Measure the firing pin hole, call Brownelll's, and replace the firing pin with something that fits better. I also avoid Winchester Silvertips in mine these days, too. When I run 9x23, I shoot reloads in mine.

 

[RSVP2RIP]

If there is any space for the primer to expand back between the firing pin and the firing pin hole, with a softer material primer it will flow back.

I don't think this is what is happening. There is no visual gap in the firing pin hole with the pin in it. The primers and the disks of primer that had jammed up the firing pin channel looked like a punch press cut a perfect circle out of them. I knew about using SR primers in the 9x23 but I would have thought Winchester would have also. Does anyone have any experience with Cor-Bons loads?