Firepower, an out of battery detonation (or excess headspace detonation) always blows the cover off as the caseing explodes outside of the chamber the pressure from the expanding gas has to go somewhere it always tries to go up first, the smoke and dull exposed boom tells ya the round exploded before being secured inside the chamber its a familiar sight with those of us who'v actually spent much time with F/A weapons, if not properly maintained ya will end up getting an out of battery detonation, the cover is popped free of the groove in the rear sight block 45,000 PSI of pressure will always take off that dust cover....... when the same thing happens in an M-16 the solid receiver top does not allow the pressure to exit up so it goes down blowing the magazine apart instead while the AK usually suffers no structural damage to the gun itself from an out of battery detonation (usually clean out the debris, clean the bolt and reassemble with straightened dust cover) the M 16 usually is taken out of action as the force of the contained explosion trashes the receiver, the dust cover of the AK is usually flipped up at the front releasing it and the shooter gets dinged but very seldom any serious injury as the dust cover acts as a venting cap while being released directing debri and gas upward while sheilding the shooters face from the debris
heres a video of an idiot with an M 16/AR 15 not bothering to actually inspect his weapon either after its trying to warn him of impending doom, just keeps hitting that forward assist and cycling the action, he got real lucky, but I suppose we can just put it off as Cr@ppy American junk aluminum guns right?
http://www.liveleak.com/view?i=481_1181023978&p=1
the "bad primer" is the bolt not going into battery most commonly from a dirty chamber but is ignored by the inexperienced un trained shooter till it kabooms on him..
Only the extremelly inexperienced could watch the AK Kaboom and come up with comments blaming the gun or its design for a failure thats very clearly operator error, those defending that operator.......... please never serv as a range master as you will very possibly get someone killed due to your inability to properly recognize such a blatant operator error not recognizing that operator error will mean you will not act to immediatly take that shooter off the line preventing injury to himself or others.
Most of these "contractors" jumping on the chance to go to Iraq don't get any actual weapons training at all and generally have very little actual experience outside of basic target plinking, I deal with ALOT of them, they get about as much training as you would if ya take your shiny new AK/AR down to the local shooting hole and just walk up to the first guy ya spot wearin BDU pants and ask em to show ya how to shoot your new gun......... thats it regardless what any of ya wanna fantasize about bein mercenaries in Iraq etc...... they don't know cr@p outside of what most learn while hunting or playing video games.....