The M1911 is a .45 caliber pistol with a 7 round magazine. It can be found in both residential and supermarket spawn locations. It's approximately two-thirds as common as a Makarov PM, but is still the second most common pistol.
ArmA2 1.62 drastically reduced the damage done by the M1911. Before the update, it was able to kill zombies with one shot; after, it now takes 4 body shots.