Here's a better one:
A guy takes the bench next to me on the range and sets up his muzzleloader for the first shot of the year. He puts a charge down the barrel and then a big lead slug over it. Drives the slug home and primes the rifle.
When he takes the shot there is a particularly load report followed by more smoke than you'd expect. He immediately puts the rifle down and complains about the excessive recoil.
There are no holes in the target.
Unable to figure out what went wrong he decides to try it again. Only this time when he drives the slug home the ramrod goes in much deeper. It only took a minute to figure out what had happened. He said that he probably forgot to unload the rifle from the previous hunting season and left it that way through the winter, spring and summer. When he loaded it (again) he had a full charge of 777 and a slug pushed down on the charge and slug that remained from the year before.
KAAAAA-BOOOOMMMMMMMMMM
Amazingly enough, the rifle withstood the abuse without damage. It was a T/C Omega, I believe.