What is a 45 caliber?

Answer 1

A ".45 caliber" can be a gun that uses .45 caliber ammunition or it can be a round of that ammunition. There are several specific calibers of small arms ammunition that are all generally called ".45 caliber." They have bullets that are roughly .454 of an inch or 454/1000 fractionally. A famous .45 caliber is the .45 Long Colt, invented in the 1870s and still popular today. It is used in revolvers. Another caliber that is the same diameter but a lot shorter in length is the .45 ACP or .45 automatic Colt pistol. It was made for use in the U.S. military's Model 1911 handgun, and it is still a popular caliber today in that gun and in other handguns. There are some rifles and carbines that use .45 caliber ammo, too.