Can you see the "crack" at the start of the first third of the top casing? This is what me and my buddy pulled out of the chamber of a vz58 (the top piece), the bottom one having been ejected on the previous shot. Thats right...: the case split completely all around its circumference upon firing, the top being left inside the chamber and the following cartridge was shoved right in it, what we have here are in fact a top half of an empty casing bearing loaded cartridge and one half of an empty casing. Now, I am no certified gunsmith but in my opinion this would keep the casing from sealing itself against the chamber and allowing quite a bit of the 60,000 some psi of pressure from the explosion to push hard against the bolt, possibly damaging the firearm or even injuring the shooter and bystanders. Numerous loads were used in the rifle and Norinco is the only brand to have ever posed any problem. In fact it is the second time we get problems with the load. My buddy had bought a case of this surplus before and returned it after noticing that a large portion of the ammo would get their primer perforated causing failed extraction every time from the gases pushing between the face and the bolt face slipping the extractor off the rim after the bolt carrier would get unlocked once the shot was fired. But last week the ammo got a second shot to prove itself worthy and a packet of 40-50(?) rounds was purchased. Same story again with the addition of this total case rupture on two occasions after what we prefered to discontinue its use (for safetys sake!). As far as the perforated primers go we verified the firing pins shape and protrusion: both perfect, and even if it would have been a pin issue, would it not have made itself apparent shooting commercial ammo? So Norinco ammo buyers beware. I was wondering what do you guys think about the casing issue reasons? Too Much powder seems the most plausible possibility, but what about a powder burning too fast say... pistol powder or could it even be something as preposterous as smaller casing dimensions? Should a sample be sent out to make sure and how dangerous is it exactly?
Norinco .223 total case failure
- Thread starter Steelplink
- Start date
Can you see the "crack" at the start of the first third of the top casing? This is what me and my buddy pulled out of the chamber of a vz58 (the top piece), the bottom one having been ejected on the previous shot. Thats right...: the case split completely all around its circumference upon firing, the top being left inside the chamber and the following cartridge was shoved right in it, what we have here are in fact a top half of an empty casing bearing loaded cartridge and one half of an empty casing. Now, I am no certified gunsmith but in my opinion this would keep the casing from sealing itself against the chamber and allowing quite a bit of the 60,000 some psi of pressure from the explosion to push hard against the bolt, possibly damaging the firearm or even injuring the shooter and bystanders. Numerous loads were used in the rifle and Norinco is the only brand to have ever posed any problem. In fact it is the second time we get problems with the load. My buddy had bought a case of this surplus before and returned it after noticing that a large portion of the ammo would get their primer perforated causing failed extraction every time from the gases pushing between the face and the bolt face slipping the extractor off the rim after the bolt carrier would get unlocked once the shot was fired. But last week the ammo got a second shot to prove itself worthy and a packet of 40-50(?) rounds was purchased. Same story again with the addition of this total case rupture on two occasions after what we prefered to discontinue its use (for safetys sake!). As far as the perforated primers go we verified the firing pins shape and protrusion: both perfect, and even if it would have been a pin issue, would it not have made itself apparent shooting commercial ammo? So Norinco ammo buyers beware. I was wondering what do you guys think about the casing issue reasons? Too Much powder seems the most plausible possibility, but what about a powder burning too fast say... pistol powder or could it even be something as preposterous as smaller casing dimensions? Should a sample be sent out to make sure and how dangerous is it exactly?
Hopefully one of these addresses links to the photo:
http://www.flickr.com/photos/98322037@N08/9178175015/
http://www.flickr.com/photos/98322037@N08/
http://www.flickr.com/photos/98322037@N08/9178175015/
http://www.flickr.com/photos/98322037@N08/
I never thought of that and never did but sure will. I just took a look at a casing that had been fired by the rifle: no bulge, just a light rim at the base of the case so maybe not to far out but too far in? might not be good enough to really tell though. but ill definitely throw the head space gauges in there or get it looked at.
I am quite surprised by the possible incompatibility issue. Would it be caused by a tolerance issues between the two manufacturers? Say.. the chamber is at the biggest that will be allowed by CZ and some casings at the smallest Norinco will allow?
AFAIR, there is some issue with CZ/VZ and norinco's ammo. There was another thread a few month ago about this.
Some of the VZ58's in 556 have soft metal where the locking block drops into. This ends up making the headspace more than it needs to be and thusly, case separations. My old man has this issue with his CSA 556 VZ58. Comes down to piss poor quality control as the CSA factory.
Nice I didnt know cases could show anything that way. ill grind the few in half tomorrow.
Thanks for your help
Hopefully head space will adjustment can take care of it then. it would be nice to be able to shoot factory ammo that is nice a cheap.
My father needs a new receiver for his rifle... The barrels are pressed in and then pinned, very hard to set them back a few thou to correct for locking block setback.
