I just watched a clip today on the outdoor channel about muzzleloaders and barrel obstructions. Using different MLs, Alan Trambil and another gentleman loaded the first one with smokeless powder. Another was loaded as normal with 150 gr of BP but the bullet was only seated 1/2 way down the barrel (mid barrel obstruction) and the 3rd was properly loaded the the muzzle was dunked into a cup of mud simulating fall without being removed.
The results were pretty dramatic. The MLs used were all inlines, a bolt action I didn't get the name of, a break open and a CVA Optima.
All 3 rifles literally exploded. The Optima with the mud in the end of the muzzle split the barrel with the top portion coming off at the breech. The bolt action with the smokeless powder as well as the mid bore obstruction exploded into too many pieces to count.
Please be careful out there. I wouldn't want to hear of any of you guys getting hurt. Don't get sidetracked when shooting - especially during the loading process.