primer blowout

[edistoriverrat]

Hey guys, something I have never noticed before until yesterday. I found about 30 of my old already fired 30-30 cases and ALL of them have the primer slightly blown out of the case, enough, so that the shell will wobble on a flat surface.
These are all factory new loads out of the box Win 150g hp, Win 130g st, Rem 170g sp core lokt, Win 170g power point.
I checked all the new rounds still in the boxes and all the primers are flush with the case like they are supposed to be.
The rifle in question my uncle gave to me was brand new, he bought it years ago and only fired it 3 times, and put it up, never to be touched again, till I got it.
It is a Marlin 30-30 336 RC. It is very accurate with any one of these rounds, at 100 yds. 5 rounds in a dime size area, anything up to 200 yds would be 5 rounds in a silver dollar size, still an excellent shot for me.
Is the primer blowout normal or is it something I should check further.
Thanks

 

[ny32182]

With the world's most accurate 30-30 I'd be hesitant to mess with anything, but, no, primers should not be backing out if everything is as it should be.

Is there evidence of gas leakage around the primer?

 

[Certaindeaf]

Is the whole primer backed out or is it cratered around the firing pin indentation?

 

[RainDodger]

Are they old cases that were reloaded many times? If so, the pockets could be loosening up. Time to throw them out, in that case.

 

[Remllez]

With groups like that I wouldn't worry about anything!! As long as the primers aren't blowing out and spraying you with hot junk....no problemo. You could win a ton of dough shooting dime size groups for $20.00 dollar bills with that 30.30 at my range for sure.
Don't sell that one!!

 

[Certaindeaf]

He says they are new factory.

If they are backed out, I'd turn on the rcmodel batlight 'cause I'm stumped.

 

[Certaindeaf]

With groups like that I wouldn't worry about anything!! As long as the primers aren't blowing out and spraying you with hot junk....no problemo. You could win a ton of dough shooting dime size groups for $20.00 dollar bills with that 30.30 at my range for sure.
Don't sell that one!!

True.. I used to do the opposite and take money from 30-30 users against my stainless Old Army. Good times.

 

[rcmodel]

See this thread from yesterday:
http://www.thehighroad.org/showthread.php?p=8010587#post8010587

rc

 

[dubbleA]

With groups like that I wouldn't worry about anything!! As long as the primers aren't blowing out and spraying you with hot junk....no problemo. You could win a ton of dough shooting dime size groups for $20.00 dollar bills with that 30.30 at my range for sure.
Don't sell that one!!

Is that with irons or with the use of a scope?

 

[Certaindeaf]

I used to get 3/4" leaned sitting with my BLR .243 and factory irons. Lee loader loaded. For regular "open" sights, those are some good sights.

 

[edistoriverrat]

Hey all,
Thanks for the replys. No to the gas leakage, the whole primer is backing out, and is not cratered. These are not reloads-they are all new, bought off the shelf and yes I used a scope, now I just have a better one. My eyes are not what they used to be. When I was somewhat younger I used to shoot at targets against my friends, never for money, yea right. Now all I use it for is deer hunting. I have only probably shot 150 rounds thru it and just never saw this before, but then I was not lookin either. I have never had any problems with the rifle so I guess I will just keep an eye on it.
Thanks again everyone for your help.

 

[Certaindeaf]

That's great. To the batcave!

 

[Shadow 7D]

30-30 is rimmed and head spaces on the rim
I would check your head space, if you load you can do that buy just seating the primer and measuring the rim plus the prime height after chambering, or by adding know width to the bullet rim until you are at a NOGO.

 

[earplug]

Head space

My firearms with excess headspace have the same problem.

 

[blarby]

2nd to RC.

I utilize a lot of .30-30 factory simply to get the brass.

Winchester seems to be the worst offender in this area by far.

I'm totally convinced it has to do with the fact that their brass weighs so much than other brands in .30-30....but have no way to explain it.