.243 Winchester - History

History

This cartridge was first introduced in 1955 for Winchester's Model 70 bolt-action and Model 88 lever-action sporting rifles and quickly gained popularity among sportsmen worldwide. Just about every major manufacturer offers rifles chambered in .243.

It was a ground-breaking development of the day, combining a very useful combination of lightweight (70 to 85 grain bullets) optimized for long-range performance for varmint hunters (groundhogs, coyotes, prairie dogs) and 90 to 105 grain bullets suitable for game up to the size of deer and pronghorn antelope. Its predecessor in the Winchester line-up and very similar .257 Roberts could have easily been selected to accomplish the same tasks, was not available factory loaded with either lighter, varmint-weight pills or pointed, long range spitzer (pointed) bullets, so it never achieved the popularity of the newer round.

Remington also saw the 6mm (.243") family as suitable for this dual-purpose use and introduced their version, the .244 Remington, in the same year (1955) based upon the .257 Roberts necked down to accept .243 bullets up to 90 grains in weight. The Winchester round remains available today whereas the .244 Remington, later renamed the 6 mm Remington with the introduction of 100 grain bullets, is far less popular even though it can push all bullet weights slightly faster with maximum loads due to the larger capacity case. The fact that the .243 Win was originally offered in a 1 in 10" rifling twist rate, a rate better able to stabilize heavier 100 and 105 grain bullets, versus the .244 Remington's 1 in 12" twist (hence the 90 grain factory offering) was also a factor in their popularity.

Since the enactment of the Deer Act 1963 in the United Kingdom, which stipulated a minimum bullet diameter of .240 in., together with minimum levels of muzzle velocity and bullet energy, the .243 is now perceived as the entry-level caliber for legal deer-stalking. Firearms that would normally be chambered in .308 Winchester/7.62x51mm NATO are sometimes available in .243 in countries – such as France and Spain – whose regulations restrict or forbid private ownership of so-called military calibers.

In a non-sporting context, bolt-action rifles chambered for the .243 were utilized by the Los Angeles Police Department's Special Weapons And Tactics (SWAT) unit during its early years.

P. O. Ackley created an improved version of this cartridge called the .243 Winchester Improved (Ackley). Like other improved cartridges, this created a steeper shoulder and blew the sides out, giving about 10% more powder capacity, and some small improvement in velocity. Both versions of the .243 cartridge are good for hunting deer.