44 & 45 caliber bullets do not have to expand to kill game. It might kill a little faster with some expanding, but isnt needed. A hardcast bullet is going to penatrate all you need. I have shot game end to end several times with cast bullets and have never recovered a bullet. The part about a bullet staying together, expanding and still penatrating applies to jacketed bullets, cast are a whole diff. game. I like to break bone with cast just to make a bigger hole with the secondary projectiles. A 44 caliber hardcast bullet will cleanly kill the biggest game in NA without expanding a bit. You do need a large meplat for best results, but you said you were using a wfn bullet so that should work no problem. Best thing about cast in pistols, rifles or muzzleloaders is that you can eat right up to the hole. Most of my cast bullets are used in the 45/70 and they dont expand and flat hammer game and I only push them to 1600fps. Handguns with hardcast kill all out of proportion of what you would think they would.