[caz223]

I would also think about doing a few other things to your gun, such as a heavier recoil spring to slow down the unlocking. I'd also think about going to a G20 and KKM barrel, if you wanted a longer barrel, the extra slide mass of the G20 would unlock later, preventing the kind of damage you're describing, esp. if you upped the recoil spring a pound of two.
I hear Lone wolf is going to release their 6" longslide for use on the G20/21 frame. Combined with a 6" KKM barrel THIS would really be the gun for something like that. You could cut your load back quite a bit and still get 1500 FPS out of it.
Or you could just use a KKM 6" 10mm barrel and do it with less stress. Shooting 10mm ammo, of course.