I had a brain fart at the range today, which is not that unusual.  I was shooting my 30 Wesson Ballard breech seated.  First I fired a case full of powder with no bullet.  Darn!  OK, run a patch through the barrel to clean out the crud.  Next shot, I must have failed to put powder in the case and there was no sound at all except the hammer fall.  I then proceeded to fire primed cases only to see why the primers were not going off, despite a plenty deep enough dimple.  After doing that 3 times with two different primer brands, I figured that maybe the firing pin was broken or something so I packed it up and headed home.  I pulled the pin and it was fine.  Next, I fired a couple of more primed cases with no 'bang'.  Looking at the primers, they were spent!  It finally dawned on me that the seated bullet was containing the sound completely.  The primers had been going off all along, just silently!   I hate it when I do dumb stuff like that.  Please don't tell anyone.

Jack

Yep that is a direct result of popping primers with a bullet still in the chamber. This brings up two questions #1 how far down did the bullet go? #2 when you opened the breech block did the trapped pressure from the primer eject the case. If not there would now be gas going past the bullet and it would be detrimental to the best of accuracy. And possibly some leading also being the end result. Also a possibility of the gas getting past the neck of the case but that has not been my own experience by also belling the mouth of the case first. When I am doing such testing in regards to gas leakage getting beyond the base of the bullet itself.