Use a chain attached to something sturdy to rotate the drum backwards. That’s worked for most of my bad jams. I had just a tire that was so jammed we couldn’t rotate the drum no matter how much we tried. Cut the chunks off that we could reach. Eventually we had to take a torch and melt it out. If you have to do that, only melt a little at a time then wet the drum so that you don’t overheat that metal and screw up the balance or temper unevenly. Also as you melt, every couple minutes try to rotate the drum. Eventually you’ll be able to back it out before you have to melt the entire thing. *Always rotate the drum backwards when working a jam!!!