Possible Dangerous Cartridges, Caution!

308 Cases with no flash holes. What a wonderful opportunity to drill them with a small flash hole. Heck even experiment. Just for funnies I calculated the total area of the two holes in 7.5x55 Swiss berdan primed cases. The total area of the two holes, IIRC, was about 1/4 that of a regular primer. So.....just maybe a very small flash hole, say .050" or so just might be the ticket. Any thoughts. On the other hand I took some 6BR cases and drilled the hole out to .080 and accuracy suffered, by quite a bit.

Donald
 
No flash hole, no pwdr burn or bullet release is expexted.

Why the the gas escaped rearward (to any extent, or bolt component damage is not uderstood). The primer has limited gas/pressure production. Being new factory loads sufficient space between the case and chamber, bullet and bore, should have been present to vent the production down the bore. A counter to that is the firinig pin driving the case shoulder against the chamber shoulder, producing sufficient seal to prevent significant foward venting. Like the bolt damage, why the case would not extact is not understood.

Contact the ammo company, and get the rifle checked out by a Pro before firing it again.
 
Here is what we know;

There is no flash hole in the primer pocket. The primer fired just like it was suppose to, but having no flash hole to flash through it went to the point of least resistance. It went back on itself, and it pushed itself out of the cartridge case against the bolt face, flattening itself out in the process.

The primer going off and the firing pin pushing forward had enough force to stick the cartridge case in the chamber. With the case stuck in the chamber the small amount of gas and debris from the primer only had one place to go, out of the ports on the side of the receiver that were put there just for such an event to prevent gases from a blown cartridge from blowing the receiver up in someones face.

When he realized that something was wrong with the cartridge because the gas and debris from the primer hit him in the face, my boss tried to open the bolt on the rifle. With the case being stuck the extractor would not hold and it chipped the edge from him trying to open and extract the stuck case.

When he was trying to push the stuck cartridge from the chamber the bullet was pushed down about half of its length into the cartridge case, being stopped by the unburnt powder still in the case and the nose of the bullet was buggered up slightly. The cartridge case was also deformed somewhat in all of this process, whether from being stuck in the chamber or being bumped / pushed from the chamber, we don't know.

Now I've read everything up to here and alot of people seem to just read part of the original statement I made about what happened, and applied alot of speculation.

I hope this helps clear up the event.

Bulletpusher
 
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I posted here about a similar incident awhile back where a factory load had the primer seated sideways. I thought it was just squished so I used it for a fouler. The rifle was a Rem 783 in .243 win. A pic of the Win factory ammo is posted here also. First row, 4th round from the end.

FWIW the little ball that the extractor slides on is a 1/8 inch ball bearing. Lost it at the range dinkin around one day. Got some replacements at a local machine shop supply place for a dime apiece.

kMHStL1.jpg
 
"primer detonation"

Primers are designed to detonate.
They are actually one of the most dangerous pieces used in loaded ammunition.

Primary impact explosives (lead styphnate) supplemented with small amount of other potent primary explosives.
Barium nitrate, tetracene, PETN, lead thiocyanate, even TNT has been added to increase the 'heat.'

Aluminum powder, zirconium for higher flame temps.
 
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