I've bent a few barrels myself. They are softer than you think. I bent a little 20 ga. Ithaca 37 that had a polychoke and shot low.

I also bent another Ithaca, a 12 ga. Flues with 30 inch barrels that shot low. I knew I was risking springing a rib but it wasn't worth a damn as is. I put the barrels across two 2x4s on the floor and put my weight on them. Took a few attempts to get the bend to set in. Now they shoot ok and the ribs are still tight.