The flint should not turn in the jaws. Have you punched teeth into the top and bottom jaws of the cock? Use a piece of leather cut from the wrist of a work glove, and clamp it hard.
To bend your cock, clamp the bottom half of the cock in copper or brass jaws in your machinist's vise, remove the top jaw screw and jaw, and with a big cresent wrench, padded again with non-ferrous metal, twist the cock outward about 1/8". Try it on the lock and see if you love it or not. If the lock has not been case hardened, there's no need for heat...bend it cold, and a little is a lot.
Interesting that Daryl beat me to it by a few seconds.