Not sure what Colt is using for an alloy in their frames now but the original frames were Coltalloy which was a aluminum-titanium mix and the frames were milled from forgings not cast.
One of my girlfriends had two Kimber ProCarry .45s, pre-firingpin safety guns. The feedramps of those guns both started gouging after only a few boxes of hollowpoint ammo. She had both frames feedramps polished and then hard chromed and that ended the problem. Also it was common practice to polish the feedramps on guns to better feed hollowpoints. Doing so to a Commander removed the hardened anodized surface exposing the softer bare aluminum...this would then get beat up with HP ammo.
Buffers...only use them for 9x23 Winchester and 10mm and usually with a full length guide rod on full size 1911s. Tried buffers on Commanders and found that especially with .45s the slide would lock back mid-magazine quite often. If one pulls back the slide of a 1911 regardless of size, the slide stop rides past the hold open notch in the frame. Put a buffer in a GM and it will still clear the notch. Put a buffer in a Commander and the slide stops right where the slide stop and notch line up. When the gun recoils and muzzle rotates up the slidestop can rotate right into the notch just as the slide stops in full recoil. I took the buffer out of the .45 Commander and never had any more problems. There was a company who made a very thin buffer just for Commanders but I have not seen them around for a while and never used one.
Bob
