This one (to my shame) is one of my own stupid things.
While augmenting the permanent training platoons manpower at the Infantry School, Singleton, we picked up the trick of cracking open a few blanks and pouring the powder down the barrel. The result is a much louder bang on the first shot which sounded much more like a real gunshot - great for the openning salvo against the exhausted trainees. The critical detail of this is we weren't issued with BFA's (black firing attachment) for our L1A1 SLRs and had to hand cock between shots.
A few months later I was enemy party for an JNCOs course on small unit tactics. Casting my mind back I remembered the trick with the additional powder, ripped off the BFA, threw in a few blanks worth of powder and replaced the BFA while waiting in ambush.
The first shot was satisfyingly loud and violent. Stunned and deafened, it took me a moment to register what had happened - the additional powder in the barrel, and tiny hole in the BFA for the gas the escape had forced the breach back and body of the weapon to partly open. Snapping the rifle closed again with some difficulty, I continued on firing in a daze.
A few hours later and it comes time to pack up an head for home. To save time we usually stripped and cleaned our weapons while in the back of the truck. Unfortunately the rifle would not open - corporals, sergeants, warrant officers all tried and failed. The force of the blast had completely jammed it and it had to be sent off to the armourers for repair. Fortunately for me nobody worked out what the real cause was....
