243 WIN Cartridge

The .243 Winchester (6.2×51.9mm) is a intermediate rifle cartridge, generally used for hunting. It is a .243-caliber bullet in a .308 Winchester case, necked down to accept .243 caliber bullets.


The .243 Winchester was introduced in 1955 for the Winchester Model 70 bolt-action and the Winchester Model 88 lever-action rifles.

Today, it is offered as an option for most rifles that can take .308 Winchester cartridges; all that is needed is a barrel change, as the length of the cartridge and rim diameter (which would affect the bolt) are nearly the same.

Design detailsEdit

The .243 Winchester, being derived from a .308 Winchester cartridge, uses a case that is the same length as the .308 case, and a bullet that is also the same length as a .308 bullet (51mm); the case is necked down to accept .243 caliber (6.2mm) bullets. The .243 is rimless, and uses a large rifle primer.

Bullet weights generally range from 55 grains to 105 grains; the lightest bullets have an average muzzle velocity of very slightly over 4,000 feet per second. Because of this, the cartridge tends to have a very flat trajectory.[1]

The .243 Winchester is best fired in a barrel with a 1:10 rifling twist, and fires with a maximum pressure of about 59,000 PSI.


The .243 Winchester is generally offered in FMJ, JHP, JSP, and ballistic tip bullets. Some bullets are boattail bullets.


  1. Select .243 Winchester on the drop down list

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.