What makes primers fail?

[P7M13]

I had 8 out of 12 rounds fail to fire today after a solid primer strike.
Curious as to what may cause this failure.
Thanks in advance.

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[Eveskcige28]

A couple weeks ago on the reloading podcast they talked in depth about this. They were saying not seating primers deep enough can cause a failure. And people will often write it off as a "dud" primer, when it's often just the primer not having a solid backing.

 

[Certaindeaf]

I had 8 out of 12 rounds fail to fire today after a solid primer strike.
Curious as to what may cause this failure.
Thanks in advance.

Were these factory or reloads? Some ammo is marketed as "green", yada yada, using a lead free primer with a very short shelf life.

 

[41mag]

I had a certain lot of WLP about 10 years ago, that suffered from anvils falling out during normal handling.... maybe 2~4%.

 

[techiej]

Did they fire on a second strike? If so then it could be the primer not being seated properly (too high).

If they won't go off on a 2nd strike then - aside from a light firing pin strike - could be either a bad primer or contamination (i.e. lube) inside the cartridge.

 

[Fishjager]

OIL. Oil will kill primers. There was a Seattle Cop who unloaded his revolver on a suspect years ago. It did not fire one time. Investigation proved that he had oiled his gun and the oil had penetrated the primer pocket. Resulting in a no fire. Almost cost him his life. His partner took the guy out. Word to the wise.

 

[DizzyJ]

I think the most common reason (as mentioned) is failure to fully seat the primer.

Worn firing pin, weak hammer spring, the firing pin binding up in the channel, and of course contamination or faulty manufacturing are possibilities as well.

Were these factory rounds or handloads?
New or old primers?

Storage conditions?

For the most part, primers are fairly resilient to contamination issues.

 

[DizzyJ]

Oh, and I believe excessive headspace can cause this as well.

 

[P7M13]

6.5x55 Swede reloads.
Storage is in sealed cabinet in the garage, 50° - 80° (winter+heat /summer)
I'm pretty focused on fully seating primers, also lets me work hand strength.
None fired on restrike.
Method: deprime, stainless wet tumble before resizing, 1 hour dry out in the oven. Use a coconut oil/alcohol lube or lanolin/IPA mix when resizing, then reload. I will lube my neck mandrel with a Q-Tip every 30 or so cases.
[edit to add] I prefer the coconut/IPA mix to the lanolin because the lanolin gums up over time, and discolors the case. Coconut does not.

Conclusions:

• Ultrasonic clean then resize then wet tumble
• Keep better notes on primer used
• Only buy primers from store.... (fixed it for ya @bbbass )

 

[bbbass]

Only buy new primers

Hmmph, never bought used primers but I doubt they would fire... I've got a whole can of them here if somebody wants them!

 

[bbbass]

I had a problem with 9mm not firing. Turned out that it was only brass that I had used a number of times. Cleaning out the primer pockets allowed the primers (which may have been harder primers) to fully seat and have not had problems since then.

 

[ma96782]

I'd be thinking......

Condition, care and storage of ammunition (including reloading products).

As for me.....

I've been shooting surplus 8mm Mauser lately. The Yugo (berdan primered, corrosive) from 1955 looked real pretty but I had a 20% failure rate. Not to fret though, as they did go off on a second strike.

Then, I tried this surplus Israeli ammo (boxer and I assume corrosive) from the 50s (not pretty looking)......well, it had a 30% failure rate. And, they wouldn't go off even with a 3rd or 4th strike. I pulled them down for the components. Powder was thrown on the grass outside.

But, the Canadian ammo (boxer primered w/ball powder, I treat it as corrosive) from the 50s was flawless.

Oh well....such is life when dealing with surplus ammo. God only knows under what conditions the ammo was stored in.

Aloha, Mark

PS.....YES, as you've reloaded it......ooops, don't like to say it but, "It could be you."

 

[Fieryotaku]

if your primers pop out just tac them in.

 

[Capn Jack]

If this was in an AR15, you might check to see if your hammer spring is in backwards.

Been there....Done that...

All bets off if it was Russian steel cased 7.62x39