the lead core out of the lightest jhp's available for a given caliber. I propane torch will suffice, and so will a coffee can set directly on the gas flame of a kitchen stove. Flux the mix good, or some lead will cling to to the copper jackets. Replace the lead with metal-bearing epoxy, use a .22lr's  powder charge as a "booster", then be sure to comress the remaining powder charge with the bullet, or the powders can mix, doing away with the booster advantage, and perhaps even becoming dangerous. Work up the loads .5 gr at a time, with the stocks off of the gun, the mag out and while wearing heavy welder's gloves. After each test shot, use a good mike to check for case bulging, and carefully check out the case rim and the primer for burring, leaking, being loose, etc. At the first sign of pressures, back off .5 gr. That's your max safe load for that slug, in those cases, in that gun, using that primer, and powder. Then chronograph it. You will be amazed at how easy it is to exceed 2000 fps with carry-autos.  Once you get the optimal powder, it is simply a matter of casting some swc's out of zinc, and transforming them into( 3 segment) prefrags. They will weigh the same as the epoxy-cored bullets do, can be driven just as fast, and they will break apart at impact. You will then have the optimal carry load in that gun. If you live in one of the states that requires a "lead core" for handgun bullets, simply epoxy a small birdshot pellet into the large, deep hollowbase that I recommend that you add to such (hp'd) slugs. Above 2000 fps, the  temporary cavity becomes capable of tearing tissues that have been weakened by multiple perforations. So even tho these slugs don't QUITE match (muzzle) velocities of the 223, their larger frontal area and this prefrag effect make up the difference. Hitting like a 223 softpoint is quite a feat for a lw Commander, but it can be done by anyone who has a couple of evenings to spend upon r and D.

And what exactly does this have to specificly do with Kimbers?

Nothing he's a

...hmmmm...
making your own self-defense ammo!
sounds great! i wonder how the jury of my peers will view this when i go to trial!
i'd guess jett3 and i have friends on the other side waiting for our "hand"gunning "ass"ets...