Friday, February 17, 2012

Vanishing primers!

Never experienced this before.

Spent case with disintegrated primer (left)
Round from the same lot that functioned normally (center)
Round from different manufacturer that functioned
without problem (right)

In shooting an SKS today, I had two rounds of six fired where cartridge primers apparently disintegrated. When it happened, smoke poured out of the rear of the rifle like the whole gun was internally on fire. Upon inspection, no damage. Just smoke.

I'd previously put 50 to 100 rounds through the rifle without a failure. The rifle is a Yugo 59/66 that, going by appearances, is in unissued condition.

I switched to ammo from another maker after today's trouble, the other maker's ammo worked just fine.

None of the rounds were military surplus. All were of commercial manufacture from Russian makers.

I'm trying to figure out if I have a batch of defective ammo. Or if I have a rifle that needs adjustment or alteration. Any suggestions?


  1. I've heard of SKSs that puncture primers, but haven't heard of one where primers blasted to smithereens.

  2. Looks like the primers weren't seated properly. I'd say the ammo is your problem.

  3. The primers were more then likely not seated well in the primer pockets and definitely were not kept in place during the firing/ejection process --- a definite ammo problem. When the rounds were ejected, the primers were also ejected away from the brass or steel casings because they did not fit properly in the primer pockets. There is no way that a metallic substance will disappear. Check some of your fired casings to see what the surviving primers look like (distortions, depth of firing pin puncture, primers sticking out of primer pocket) and this may give you an indication of problems with your ammo manufacturer's lot. You may want to stay permanently clear of the brand of ammo that is causing the problems. Also, check the bolt face for any strange primer/case base marks. You also might want to have a qualified gunsmith check the headspace on this weapon.

    1. Inspecting other cartridges in the box the defectives came from, there's no sign of the usual lacquer seal usually visible on steel case Russian ammo. In checking other boxes from the same maker, a red lacquer seal around the primer is clearly visible. I'm chalking this up to bad ammo. Gun checked okay with headspace gauges.