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View Full Version : Help with 7mag ONLY denting primers


junkout
05-08-2015, 07:00 PM
I have an older Savage110 chambered in 7mag. It's will not fire and only dents the primers. Now and again it will fire. Inspected firing pen and it is clean with no oil, l bolt appears to be in order. I'm thinking the firing pen must be worn down as it doesn't appear broken. Is there a measurement or a way to check and see if it is within spec? I know the firing pen needs. 050" protrusion to ignite a case but I don't know how to check it.... Any other ideas that will help fix this problem would be appreciated.
Maine-iac
05-08-2015, 08:24 PM
Might be tired. Not an expensive replacement. $20 tops. I would bet that solves your problem.
Robinhood
05-08-2015, 09:36 PM
You need to disassemble your bolt and clean it thoroughly. While reassembling it, oil it with some quality gun il or better. Before you install the BAS, roll the cocking pin into the fired position. install the BAS until you get spring pressure.

Measure the amount the firing pin protrudes from the face of the bolt head. Dial calipers will work if you know how to use them with depth mic being a better choice. You will get a baseline measuring to the face and then subtract the dimension measured to the firing pin. That will be your protrusion. I'm thinking .035 to .045 is good. You can go a little more but I would not go much less.

I think there is a FAQ on how to adjust a pin.
junkout
05-08-2015, 10:30 PM
Sounds good. I'll see if I can find it. Thanks
BillPa
05-09-2015, 12:21 AM
? I know the firing pen needs. 050" protrusion to ignite a case but I don't know how to check it.... Any other ideas that will help fix this problem would be appreciated.


Actually you only need .030"-.035". How to measure it? Take two measurements, one to the boltface and another to the pin in the fired position both from the end of the bolt head. The different between the two is the amount of protrusion.
http://i59.tinypic.com/nqcnc5.jpg

I use a depth mic but you can use the tail end of a caliper.

Inconsistent primer ignition generally is a result of something padding the pin fall, rarely is its a weak spring. It could the sear touching the stock or as simple as the trigger-sear in need of a good cleaning.

Bill