Shooters Forum banner

1 - 2 of 2 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Hey folks,
I'm concerned about my old Win Mod 94, it always leaves a cratered primer after I shoot, be it factory ammo or reloads. I've tried lighter loads, but it still does the same thing. It's done this since I first got it, I don't think it is from high pressure. Any ideas on what is causing the problem, and how I should fix it? Should I even worry about it?
 

·
Super Moderator
Joined
·
3,366 Posts
The most likely culprit is the diameter of the hole in the face of the breechblock for the firing pin.  One of two things... either the hole is oversize, or the firing pin is slightly undersize in diameter.  This will allow a significant flow of brass from the primer cup (yes they are brass, just nickel plated) back around the firing pin, and give the initial appearance of exessive pressures.  If the problem is really severe, an oversize diameter firing pin might be in order, or machining the boltface to accept a bushing that is drilled with a tighter tolerance hole for the firing pin.   Either fix will cure the problem.

Now, for the practical side of me!  If you aren't shooting excessive pressure loads, and you know that to be true by measuring case head expansion, and you have run a go/no-go headspace gauge through the gun and know that there isn't an excessive headspace condition (this can cause what you are experiencing as well... but not usually), then I would continue to shoot and enjoy the gun!  I see no reason to go to the expense and trouble of rectifying a cratered primer symptom, unless it is severe enough to cause primer leaks.

Just my opinion, but I think after checking pressures and headspace, I'd shoot the critter!

God Bless,

Marshall
 
1 - 2 of 2 Posts
Top