barrel straighting

[D. Taylor Sapergia]

I can seen I've been remiss...after I took the clamp off, both my bench, and the barrel, returned to straight.  Bending this barrel as in the photo did nothing to change its deflection.  I think it would have made a good longbow, if I was able to draw it.

[Mark Elliott]

I had to bend a fowler barrel once to sight it in.   It was quite instructive.     I made some V blocks to go in my vise to bend the barrel.     My little vise wouldn't budge it.   I ended up clamping the barrel very securely to the top of my bench with the bend point at the edge.   I would lean on the free end of the barrel with my considerable weight and kinda bounce it into a slight bend.   I would have to deflect the free end of the barrel several inches to get even the slightest permanent deflection in the barrel.   After that,  I never concerned myself about a barrel being straight again.    I think you really need a commercial parts press to properly bend a barrel.   You have to put a LOT of pressure on it.     

[bob in the woods]

I had a .36 cal  3/4 in barrel that was part of a kit I got from Jack Garner 21 years ago. The rear sight was drifted to the right all the way and the front was to the left all the way to get it on target. I called Jack and he told me to bend the barrel straight.  A piece of 8 in timber on either end, and a monstrous c clamp where I thought it needed to be. A 4 in deflection did nothing !   I was amazed a t how much I had to crank that clamp to get any result.   Now, I always check a barrel first to see if there is any variance , and if so try to index this so the "bend " is up/down rather than sideways.  That way it's easier to fix , as the sights will usually compensate for it being a little off.  Ie...the fix when bending isn't as critical . Close will do.   
After experiencing what it takes to actually bend a barrel, I no longer worry about accidentally bending one in the field.