I had, for awhile, a Colt Gold Cup in .45 ACP. It was a pretty good gun for crows and groundhog out to about seventy five yards, or so. I handloaded my ammunition and used the 185 gr. Sierra JHC (Jacketed Hollow Cavity) bullet. This did a good job on small varmints. Also used some Winchester factory Silvertips to good advantage.
I've heard of folks taking deer with the M1911, but I'd rather stick with the .44 Magnum for that kind of work.