Author Topic: Popped Primer Problem (update 6-28-13 Found a CURE)  (Read 67571 times)

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murray

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Re: Popped Primer Problem (update 6-28-13 Found a CURE)
« Reply #180 on: October 06, 2019, 12:23:27 PM »
It's been a couple of years since we posted here, Eleven years since the Thread was started, and while a lot of things have changed over the years, one thing seems to remain the same. Imported steel cased Berdan primed ammo is subject to popping primer pieces into and often through the firing pin hole on the bolt face.

While the top photos on this page of our site show damage to an original firing pin, and back on page 8 of this thread is another, we're the first to admit it can damage our FP as well. Since we changed to 17-4 SS material in Jan 2014, none have been reported broken, except those sold prior to that time. But even the newer ones can be slightly bent, and spring is always instantly ruined and often fully collapsed.
https://murraysguns.com/popped-primer-problems/

Just like this most recent customer, that had our older FP Kit, those primer failures finally shut his gun down. FP broken, spring ruined, and 7 pieces of primer came out of his bolt when we disassembled.

But we did the Neck & Throat service when we installed his new Firing Pin Kit, and we'll simply copy and paste his most recent comments to us.

Ben,

The parts arrived yesterday. I am very happy with everything you have done for me on this job from A-Z.

I shot the rifle at the range yesterday.

It shoots 1-inch groups now with the same ammo that I was using when it popped the primers.

I've gone from a gun I was ready to scrap. Too a gun I will enjoy for years to come.

Your customer service was truly a pleasure for me.

Your workmanship on my parts superb!

The price of the service is more than fair.

Again I am very happy with Murray' Gunsmithing

Thank you!

PM, Utah


The price for the service has gone up $2.50 but it's worth every penny, in fact we're now saying "makes your SKS run like an AK." And while we don't lay claim to any accuracy improvement, this is the 3rd or 4th report saying just that.  8)

2nd pic shows the winner for the most Popped Primers found inside a Bolt. (and it was still running, just misfired occasionally) And notice how our newer 17-4 SS Firing Pin held up much better, even though the hot gases blowing back through the Bolt had totally fried the Spring, and battered the FP significantly, yet it still did not break. (no FP has ever broken that was shipped after 1-29-14)

« Last Edit: November 23, 2019, 04:57:25 PM by murray »
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If you feed it junk ammo, why should you expect filet mignon results? Well now you can, with our new "Neck & Throat" chamber reaming service!

Andronicus

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Re: Popped Primer Problem (update 6-28-13 Found a CURE)
« Reply #181 on: October 07, 2019, 02:58:03 PM »
If I understand the problem, popped primers are a result of the face of the bolt protruding in a volcano like way.  Are these protrusions a result of excessive dry firing?
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murray

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Re: Popped Primer Problem (update 6-28-13 Found a CURE)
« Reply #182 on: October 07, 2019, 03:39:13 PM »
Even an original firing pin will cause the slight volcano like raised ring around the FP hole on the Bolt face, when it is dry fired excessively. But that is Not the "cause" of these primer failures. You can use any firing pin you choose, smooth the Bolt face perfectly flat and countersink the edge of the FP hole, polish the tip of the firing pin, insure there is a nominal .050" to .055" FP protrusion, and you can still have the primer failures that we call "Popped Primers." We believe it helps to address the bolt face, but it is not the root cause.

Spikes in the peak chamber pressure are "exploding" these pieces of primer into and often through the FP hole on the Bolt face, at almost exactly the same instant as the bullet going out the muzzle end of the barrel. Once we do the Neck & Throat service, the spikes in the peak chamber pressure are eliminated and no more primer failures. Simple as that. 

Our FP Kit is exactly like any "original" firing pin in that it has no bearing on these primer failures. It can happen no matter what firing pin is used, and no matter what condition the bolt face is in. But with ours, you have a 100% guarantee of no "Slam Fires."

https://murraysguns.com/shop/

If you feed it junk ammo, why should you expect filet mignon results? Well now you can, with our new "Neck & Throat" chamber reaming service!

murray

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Re: Popped Primer Problem (update 6-28-13 Found a CURE)
« Reply #183 on: November 23, 2019, 05:04:00 PM »
Edited above with photo of the winner of: The Most Popped Primers Found In A Bolt Award

(winner?)   :roll:
https://murraysguns.com/shop/

If you feed it junk ammo, why should you expect filet mignon results? Well now you can, with our new "Neck & Throat" chamber reaming service!