5.56 primer issue

The place to discuss ammunition, reloading, ballistics, loads, and chamberings.
Post Reply
Precision
Posts: 5272
Joined: Wed Aug 20, 2008 6:01 pm

5.56 primer issue

Post by Precision »

So I had an odd thing happen at the range today.

I took a former student to the range and we warmed up at the rimfire range, then slid over to the high power range so he could get some time behind my new varmint AR.

We are doing some slow fire from a front rest at 100 yards. The first 10 or so rounds are 77 gr Berger reloads, then about 10 hornady 75 gr reloads. Then just to show point of impact difference I put in 4 of the Lake City 55 gr factory rounds that I had leftover from a previous session.

I reload, so the guy a few benches over, was setting the brass that rolled his way on the bench between us. After the last of the 55 gr factory bullets went bang, he handed me two that flew past.

One had no primer. It was still warm so I know it wasn't one left by someone else. At first, I though I had over done the powder on one. Then he found the primer. The primer was gold. All my reloads have silver primers. On closer inspection, the primer pocket was no longer round, it was visibly ovoid.

Since we found the primer right near where the brass landed, we assume it fell out on impact. The primer can be dropped back into place and gravity will make it fall out again. It certainly wasn't that loose before we shot it.

What the hell happened? Factory over charge? slightly ovoid primer pocket that expanded on ignition?

Picture to follow.
"Those who hammer their guns into plows will plow for those who do not." ~Thomas Jefferson
My little part of the blogosphere. http://blogletitburn.wordpress.com/
Precision
Posts: 5272
Joined: Wed Aug 20, 2008 6:01 pm

Re: 5.56 primer issue

Post by Precision »

Ovoid 2.jpg
It is more obvious in the first picture. The second one might be too out of focus. Damn camera on my phone sucks for macro work. :D
Ovoid primer pocket.jpg
You do not have the required permissions to view the files attached to this post.
"Those who hammer their guns into plows will plow for those who do not." ~Thomas Jefferson
My little part of the blogosphere. http://blogletitburn.wordpress.com/
User avatar
PawPaw
Posts: 4493
Joined: Fri Jan 02, 2009 8:19 pm

Re: 5.56 primer issue

Post by PawPaw »

Bad primer pocket. It happens. I wouldn't obsess over it.
Dennis Dezendorf
PawPaw's House
Aesop
Posts: 6149
Joined: Sat Apr 27, 2013 9:17 am

Re: 5.56 primer issue

Post by Aesop »

With current production rates, factories eff up.

Even back before the current 3-shifts-a-day 24/7/forever nonsense.
Back when full cases were readily acquired, out of a full case of pistol loads in .45, I had one with the primer installed backwards, and one that split from throat to rim, on new brass.
I assume that rate of bad rounds is the norm.

That's why I pay attention for squib loads, because those'll really make a day at the range interesting. :shock:
"There are four types of homicide: felonious, accidental, justifiable, and praiseworthy." -Ambrose Bierce, "The Devil's Dictionary"
Precision
Posts: 5272
Joined: Wed Aug 20, 2008 6:01 pm

Re: 5.56 primer issue

Post by Precision »

ok.

At first I thought I had F'ed the pooch in reloading. Then I realized it was factory ammo. Then I was really confused with the ovoid pocket.

Poor quality control is not super comforting, but No damage seems to have been done, so... obsessing is over.
"Those who hammer their guns into plows will plow for those who do not." ~Thomas Jefferson
My little part of the blogosphere. http://blogletitburn.wordpress.com/
User avatar
First Shirt
Posts: 4378
Joined: Mon Aug 18, 2008 11:32 pm

Re: 5.56 primer issue

Post by First Shirt »

One of my stepson-in-laws had a similar incident with a .270 Win. He had been counseled, at some length, about the importance of saving brass, and asked about a case (Remington, IIRC) that had dumped it's primer somewhere at the range.

I told him that this is what you get for buying Remington ammo, after I done told you twicet that the juice ain't worth the squeeze.

They're slow, but they can be taught.
But there ain't many troubles that a man caint fix, with seven hundred dollars and a thirty ought six."
Lindy Cooper Wisdom
Post Reply