The .244 H&H Magnum was introduced in 1955. It could be considered the final word in 6mm cartridges. As factory loaded it exceeds the muzzle velocity (MV) of the .240 Weatherby Magnum by about 100 fps. Loaded to the same pressure with modern powders it would beat the hot Weatherby Magnum by more, as it has a longer and fatter case of considerably greater capacity.

The other modern 6mm magnum, the .243 WSSM of 2003 pales in comparison to real magnums like the .240 Weatherby and .244 Holland & Holland. (See my article "Compared: The .243 WSSM and .240 Weatherby Magnum.")

The .244 is based on the full length .375 Magnum case with less body taper and a shortened neck. The rim diameter is the usual .532" of magnum cartridges. The base diameter just forward of the belt is .508" and the shoulder diameter is .445". The case length is 2.78" and the cartridge overall length (COL) is 3.58". Bullet diameter is .243-.244", and large rifle magnum primers are required.

The British factory ballistics called for a 100 grain bullet at a MV of 3500 fps and muzzle energy (ME) of 2725 ft. lbs. This was achieved by some 74 grains of an unspecified smokeless powder (not Cordite). At 200 yards the remaining velocity was 2970 fps and the kinetic energy 1980 ft. lbs.

I do not know the ballistic coefficient of the British bullet, but the trajectory of that load using a 100 grain Speer Grand Slam bullet (BC .351) would look like this: +2.3" at 100 yards, +3" at 165 yards, +2.7" at 200 yards, and -3" at 330 yards. The maximum point blank range (+/- 3") would thus be 330 yards, putting the .244 H&H Mag. near the top of ultra-long range cartridges.

There is always a price to be paid for that kind of performance, and in the case of the .244 Magnum that meant excessive recoil and muzzle blast for a .24 caliber cartridge and short barrel life. Forcing that much incandescent gas through a small bore cannot be good for the barrel.

As it happened, shooters all over the world for once rewarded moderation and good design by laying down their hard earned cash for .243 and 6mm rifles, while sales of Holland's super magnum lagged. Today the .244 H&H Magnum is, as far as I can determine, obsolete. Given sufficient monetary incentive, however, Holland & Holland might be willing to make one up. No factory loaded ammunition or production rifles are offered in the caliber.

If so, reloads would be a matter of research and educated guesswork. Obviously, the slowest burning powders would be called for. I'd probably start with .240 Weatherby loads using RL-25 or IMR 7828 powder behind a 100-105 grain bullet and work up gradually.

Nevertheless, the .244 H&H Magnum represents some sort of high water mark in the development of the 6mm cartridge. To use an aviation analogy, you could think of it as the Concorde of rifle cartridges.

Note: An article about the .244 H&H Mag. and the .240 Apex can be found on the Rifle Cartridge Page.