Firing Pin effect on ignition

I dare say Mr Kevin Gullette seems to show an image of a truly pierced primer :) or at least not the typical blanked primer.

I'll not go into what may have occurred to produce such an effect but will state with fair certainty that it had nothing to do with "excess protrusion"

That said, thank you Kevin, you've broadened my horizon this day........this has absolutely no bearing on what's 99.99% of the time referred to as a "pierced primer" (every other instance in this or any other thread on BRC refers to blanking) but that thar shore appears to be a punctured primer, and without any sort of description I'm guessing Kevin that this rifle has somehow been modified (hacked) to produce this effect? Or was it a one-off? A weak spot in the primer cup...a fluke?

I don't see a previous post.

al
 
Oooops, Kevin I found the previous post.... sorry, I just don't keep a comprehensive overview of this site anymore.

My bad

al
 
Wilbur said:
I was shooting a fairly hot load at the nationals and was doing pretty good - good enough not to change anything. Every now and then I'd have a hole in the primer and didn't think much of it as, again, I was shooting pretty darn good. I looked at my bolt face and realized that the firing pin hole was plugged with a piece of primer so I took it apart to clean it. Turns out, there was a whole bunch of pieces all about - two or three in the firing pin hole. I cleaned the pieces out and proceeded to shoot poorly for the remainder of the nationals. I've often wondered what actually happened there!! Well, I say often, but I've tried to block that incident out as much as possible.
Click to expand...

Classic blanking, the pieces in the bolt are simple proof that you were over-loaded. They're sheared by the fp hole and blown into the bolt by the excess pressure. "What happened here" is running near unto max with thrown charges. Some threw heavy ....... "POP".....
 
Al sorry to disagree but my buddys rifle had no signs of pressure, and hasn't had a problem since. It's just a bad primer like you mentioned! Oh there CCI primers. Never had a federal do that and I've run some hot loads over the years.

Joe Salt
 
I had an incident that happened at a large long range match that I blew numerous primers over the weekend...ruined about 60 pieces(primer pockets) of fresh fire formed Dasher brass. So bad, that I opened the bolt and the primer fell out in the load port! One actually made it into the the lug recess that I did not know about and fired 10 record rounds! All this in a custom action that was running the same tried and true load. Nothing changed other than a few degrees warmer. I thought too that it was a pressure issue. Spent weeks trying to trouble shoot from buying a borescope to testing several lots of powder, chronographing, testing other bullets, charges, barrels....etc. Finally hit me...maybe I should install that new firing pin spring that I had in my box. Evidently, I was saving it for a rainy day, LOL. Like a light switch, problem totally solved. In the end, turns out that it was NOT a pressure problem, but ignition. If it goes bang, does not mean that you have strong consistent ignition. This is one of the most over looked issues that guys aren't aware of and can create many problems that are misdiagnosed. Since then, I have upgraded my ignition system and will keep a fresh spring on hand at all times, LOL. Edit added: Would also like to add, the gun shot well....so well it took the 2 gun group agg for the weekend! So, even though it shoots good, does not mean there isn't a problem.
 
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Well, I'll admit that a fresh spring doesn't hurt. Changed mine to a new one. It didn't hurt/ help my groups, but it did solve some primer flow. Also for those that are interested, 29.9gr of IMR4166 and a 105gr Amax is a killer combo. Adam
 
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