Assembled new M-16 dealer sample last night, took it out to test fire.  Most of my regular ammo (Wolfe) is already packed away for trip to Bulletfest so grabbed some misc. loose rounds and headed across the road.   Fired a few rounds semi and worked OK.  Flipped the switch to rock 'n roll and a single round went off.  Pulled the handle, had a repeat.  Took it apart and checked the rings etc, found loose gas key.  Rescrewed it and staked in place.  Tried again - same problem.  A few inspections later, I get serious.  Pulled the gas tube, clear.  Same for the port.  Put air pressure in the gas tube while stuck in the bolt carrier to test for leaks - none.  Blocked bolt / key passage maybe?  What with having the loose key, anything could have happened.  Pulled bolt from carrier and applied air. Plugged tite.  Removed my well staked screws for a look.  Key is the problem.  Damn PRIMER blew out, turned firing pin side forward, found it's way into the key and got driven home by the gas tube!!!  Amazing - to put that thing in there on purpose and drive in place would have been tough!  In the field it would have been the end of your day (or life in combat).  Had to drill the sucker out.  Still can't believe it; what are the odds?

Ammo was brass case, green sealer, silver colored primer, no primer crimp.  Headstamp was 5.56  H8.  Bullet crimp was the segmented kind.  Can anyone ID headstamp??  

Serves me right for deviating from my normal Wolfe!!!!!!!!!!

i've had blown primer cups land everywhere else.

in the gas key?!?!?! wild.

i'm running only wolf 62 and 55 grian in the m4 m-16. 4 cases and not a single problem.

it also ate some of that crappy izzy junk and some of that great swiss stuff.

3 days until we air them out at bulletfest!

Are you crazy useing wolf!!!!   Got anymore!

 Bob [:D]