doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Split Primers???

So I just purchased a Varney Carron helistop 16 gauge, and I put it through some paces yesterday. Maybe the 20th shell I pulled out of the barrel, I didn't take much notice of a little black spot on the primer, a piece of dirt... some unburnt powder.. whatever. Then 20 rounds later, another shell with a blackened primer. So I took a closer look and all I can deduce is that the firing pin is too long and the primer is splitting open allowing some form of "blowback" (im not really sure what to call it). I continued to shoot but when it happened a third time I called it quits. It happened in both barrels, with different shells each time.

Has anyone come across this or have any advice on what to do about it? can I just shorten the pins a few thousandths? or is it something that I shouldn't even worry about?

I have not had that happen with a shotgun, but have had it happen with a revolver. The firing pin was too long and was piercing the primers on every shell. I took a file to the firing pin and after each stroke of the file I dry fired the gun on an empty case that still had the fired primer in it. I continued until the firing pin no longer pierced the primer.

That your shotgun only does this intermittently makes me wonder if the problem is the firing pins or something else. If the firing pins are too long, it should pierce the primer every time or almost every tiime.

I disassembled the entire thing yesterday once I got home to see if I could find anything out of the ordinary. Long story short I couldn't diagnose anything that would cause the issue. The only other thing I can come up with is maybe the hammer springs are too stout? again I've never encountered that but maybe the hammers are simply falling too hard?

how much do the pins protrude the breech face?

I don't have the gun on hand right now but I can measure that up when I get home. They didn't look like they protruded any further than anything else I've seen, but I can get hard numbers for you later today or tomorrow

Are you using 2 3/4" shells in 2 1/2" chambers? Not necssarily the cause, alone, but could contribute.
Mike

Mike,
That's a negative. I measured up the chambers before I took it out to shoot. The forcing cones look a bit rough (unpolished) compared to the rest of the bore. My guess is the chambers have been reamed.

What ammo were you using?
Some with Cheddite primers have been known to spit
The Remington ammo seems to have the hardest primers
Was the ammo new or old?
Mike

I quit using Remington Gun Club shells after several failures to fire were due to a short firing pin in my K-80 according to Remington. The same gun was pierceing primers on another batch of gun Clubs. I was talking to a major reloading dealer from Houston and he said he stopped selling Gun Club for that reason.
Try a different brand of shells, it may help

bill

Mike
Ammo was brand new.
Remington Game Loads - 1oz - 7 1/2 and 6