go to: http://stevespages.com/page7b.htm
If you mean the standard Caliber of a 1911 model colt pistol,then this was chambered in the caliber .45ACP.
Automatic Colt Pistol. Colt invented the .45 Auto and thus had the right to name it.
Caliber .45 Automatic Colt Pistol.
Rifle or pistol?
22 caliber ammo
The caliber of this weapon is .45 ACP, or it's full name is .45 Automatic Colt Pistol.
1911
100-10000 USD
Go to Colt's web site and request an owner's manual.
What is the value of 1903 colt pocket pistol.32 calibre?
@1914
100-800 USD