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I have a GEW 98 mauser in 7X57. I been noticing deeper primer punches than I see in other rifles. This morning it actually punched thru a primer. Can you adjust the firing pin in this mauser? thanks, Roger in Texas
 

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Any competent gunsmith can adjust firing pin protrusion, whether too short or too long, but I will say that in 44 years of gunsmithing I have never encountered the problem in a Mauser. I suppose it's possible that someone may have replaced yours with one that is slightly too long. Are you maybe shooting handloads that are a little warm? I think you should take the rifle to a good gunsmith and have him check it over, especially protrusion and headspace. Goatwhiskers the Elder
 

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I am shooting a handload using 160 Sierra Spire with 45.3 gr of IMR 4350.
According to my book, that is very close to a maximum charge. Depending on your seating depth, chamber dimensions, or any of a number of variables, it may be too "hot" for your gun. I would suggest backing off .5 - 1.0 grain, loading up 20 rounds and shooting them to see if your primer pin is still too long. The odds are very good that it isn't your firing pin, at all.

If you find that to be the case, you may look at your seating depth because if you can increase your COL by as little as .020" you might alleviate the problem.
 

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The Hog Whisperer (Administrator)
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You might have the odd soft primer or two, also. If the tip is rounded, well, a mauser really thumps the primers..... they are meant to do that.
 

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broom_jm

That sounds like good advice. I'll back off to 43.2 grs of IMR 4350 (or 2500 fps in 4th edition Sierra book) and see how that cooks. As a second option, my current COL is 3.104. If I need to, I'll try to nudge it up to 3.124. Thanks for your advice. Roger in Texas
 

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broom_jm

That sounds like good advice. I'll back off to 43.2 grs of IMR 4350 (or 2500 fps in 4th edition Sierra book) and see how that cooks. As a second option, my current COL is 3.104. If I need to, I'll try to nudge it up to 3.124. Thanks for your advice. Roger in Texas
You're quite welcome...just be sure to report back to us, so we can all learn from what you find. I have been helped out several times since I joined this site, so I'm glad to pay it forward, when I can.
 

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Discussion Starter #8
You might have the odd soft primer or two, also. If the tip is rounded, well, a mauser really thumps the primers..... they are meant to do that.
Mike -- you may have a good point there because I fired two more rounds after that primer popped and they worked just fine. After this topic help, I measured how far it extended and it is within tolerance....so it may be too close to a hot load. thanks for your input, Roger
 

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The Troll Whisperer (Moderator)
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Mike most probably found the answer to your problem, but be aware sometimes there's such a thing as a bad primer.

Several years back I ran into problems with a brick of Remington 9 1/2 primers - pierced and holes blown in the radius of the cup. Loads were well within published limits. Got another brand of primers, used the same load and things worked fine. The remaining brick of primers were deactivated in a bucket of diesel, given a couple weeks of soaking and buried.
 

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In the link below there is a chart of various primers and their properties, such as thickness of the metal used for the cup. Also, keep in mind that primer manufacturers can, and do, change primers w/o necessarily conveying that to reloaders.

A combined effect of soft primer cup and a pretty hot load can be causing the problem you're seeing. Remember to reduce your charge and work back up, if you change to a different primer.

http://www.jamescalhoon.com/primers_and_pressure.php
 
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