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Tazmanian
08-04-2013, 03:08 AM
hi all...been getting some soft strikes on primers and wondering if there is a way to strip and clean a centre fire bolt...

and have heard that "polishing" firing pin helps as well...how does one do that

cheers in advance

FW Conch
08-04-2013, 07:12 PM
Before you do anything, if you haven't already, make sure you really have light strikes. The best way to do this is to chamber a fired shell and pull the trigger. This will show what the true firing pin strike is. With a live shell, the powder explosion goes off, swells the case out to the dimensions of the chamber in all directions, the bullet resists going forward, and the primer tries to become part of the breach face! If the load is a little "hot", the primer tries to go in the firing pin hole and pierce itself on the firing pin. Something like that?:) So, when the case is ejected, the primer has been through too much trauma to tell if it is a light strike or not. It could be, when you drop the hammer on the fired case, you may have a "huge" pin strike:)! Good Luck..... Jim

Joe L
08-04-2013, 08:20 PM
Tazmanian--you didn't just change the stock or do anything around the bolt handle did you? If the bolt handle won't rotate down all the way due to interference with the stock, you can get a light hit. I have seen that happen when stocks were changed out and the bolt handle slot was just a little off. A little work with a file will clean it right up. Just thought I would offer up that experience if you don't find anything wrong with the firing pin assembly itself.

Joe

Tazmanian
08-10-2013, 02:50 AM
more info guys....

today at the range I tried a different ammo that is American eagle 50gr ballistic tipped....the same thing happened...some went bang with an average firing pin strike indent but some didn't go bang and the very small indent appeared.....one of the very experienced guys at the range said it could be that the rounds are just a little short and move when struck....he said he had the problem with American eagle before so doesn't use at all... bought some Winchester 55gr soft points ( great on kangaroo's ) to try next time....

stangfish
08-10-2013, 03:37 AM
He may be correct. An inexpensive case headspace inspection tool would expose that issue.

Nor Cal Mikie
08-10-2013, 09:30 AM
You tried "different ammo"? Must be factory loaded? First place to look would be ammo being too short for "your" chamber.
Firing pin pushes the round forward in the chamber and you get what you're calling "soft strikes" on the primer The OAL of the round may be too short. If you have a way, pull the bullet out a ittle in the case making the OAL a little longer. The bullet will be against the lands and that will keep the base of the case against the bolt face and not get pushed forward by the firing pin. If that fired brass was reloaded and fired, it has been blown out to match the measurements of the chamber and you wouldn't have anymore problems. One of the advantages of rolling your own ammo.

Tazmanian
08-10-2013, 12:31 PM
thanks....different ammo meant another type of factory loads.....

jonbearman
08-10-2013, 05:11 PM
For safetys sake have a gunsmith check the headspace,it only takes a few minutes.