Grapeshot,
Excellent thought! I recall that same scenerio several years ago in SHOOT magazine in that 3 cowboys who owned 44-40 revolvers blew them all up.
They determined that to be the cause. One would think that after the first mishap, they would have really done some digging to find out why(?). It wasn't until after the 3rd revolver let go that they determined the cause....... 2 bullets in a case.
In this case though, the cartridge is the 45 Colt and likely, the bulge of the bottom bullet would not allow the cartridge to be chambered. (After I learned of the above situation, I tried seating 2 bullets in a 45 Colt case. The bulge from the base of the bottom bullet was really noticeable and the cartridge would not come close to being chambered.)
Beauregard had indicated on another website that he loaded the bullets individually by hand on his progressive press and thus there were not two bullets in the case. I was very happy to hear that he was not injured.
The likely culprit was a double charged case. I hate to admit that I did that once. I was loading Hodgdon's Universal under a 250 gr bullet. I was shooting a side match (reduced steel buffaloes ot to 125 yards) when one of the shots did not sound right. I immediately knew there was something wrong when I tried to eject the cartridge. The lever on my Marlin Cowboy rifle would not budge.
I used a cleaning rod to remove the case. The primer was really flat and the case rim/head had increased by .005" in diameter.
THANKFULLY, the Marlin held and there was no damage to the rifle. I called a fellow I knew who worked at the Hodgdon's ballistic lab and he estimated the pressure at close to 60,000 CUP.
I recalled what happened. Sometimes I double charge a case in a loading block of 50 to see what a double charged case looks like for reference. I then dump the powder back into the powder measure. On the day that I loaded that block of 50 I must have been called away to the phone........
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