MISFIRES

[cj8vet]

I searched misfires, read those older threads,Just checking to see if anyone else wants to comment .
Stiller TAC30, 6BRX, lapua Brass,Varget, CCI-450,Lee HandPriming tool with sinclair stainless case holder.FP protrusion about60thous.,shoulder setback about 3thous., 4 misfires outta last 1000 rounds, tried each 2x, removed the last one and cked it with a hammer and anvil-(safety precautions taken)-Good POP,--1st 3 misfires were in practice,with 5x fired brass, last one was at a match-(GRR!, no spare rounds allowed at line) with 2x fired brass. all primers seem to be seated appropriate depth,what is happening? more measurments? from???
next best primer for varget and BRX/Dashers?
Thanks
Mark
cj8vet@gmail.com

 

[ireload2]

It has to be your rifle. Have you ever had a fubar because the bolt handle was up a little?
I say it has to be your rifle because in 50 years of shooting I have never had a dud primer and I have fired a lot of cheap junky rifles. Double check the firing pin protrusion. Is there any chance of varnish or excess lube on you mainspring?

 

[s100whunter]

I would change firing pin spring,seems like this is becoming more frequent of a problem

 

[Tiratore]

My only rash of misfires was many years ago. There was a mismatch (?) between my Stiller Viper DP and the particular Jewell trigger I was using. To make a long story short, I measured the striker fall and found it short. Mr. Stiller provided a trigger hanger without pin holes. By drilling new holes some 0.030 (my memory isn't all that great - something like that) further back, the problem was solved. That problem only showed up in really cold weather (Dunham's Bay).

At this weekend's NYS IBS Score match, a shooter had a similar problem, solved by replacing his Bix trigger and hanger with a spare Jewell and its hanger.

A combination of primer design, headspace, depth of primer, spring strength, and a too-far-forward trigger position attributed to an unfortunate tolerance stack-up apparently combined to produce the problems. Fixing the firing pin fall overcame all.

 

[DaveTooley]

This topic should be pinned in gunsmithing and reloading.
Leading causes for misfired primers.
#1 Primer not seated deep/hard enough to sensitize it.
#1A primer pockets cut too deep resulting in #1. Why cut them at all?
#2 Not enough energy transferred from the firing pin to the primer. Short fall, fatigued spring, improper alignment of the ignition system, etc.
#3 Case body is short allowing the ejector to push the case forward away from the firing pin. Think about fire forming Ack Imp cases.
#4 Firing pin protrusion a distant fourth unless you have debris inside the bolt.