The .333 OKH

By Chuck Hawks

The idea of necking-up the .30-06 case to take .33 caliber bullets is certainly not a new one. Various .33-06 wildcats have been around for decades. One of the better known versions is the .333 OKH, which received a lot of praise in print from gun writer Elmer Keith who is the "K" in OKH. (The "O" represents Charles O'Neil and the "H" represents Don Hopkins, the cartridge's co-developers.)

O'Neil, Keith, and Hopkins used .333" bullets from the relatively rare .333 Jeffery, a British medium bore cartridge. Other .33-06 wildcats used bullets from the (now obsolete) .33 Winchester cartridge. None of these .33 caliber bullets were readily available to reloaders, a fact that curtailed the popularity of the various .33-06 wildcats even though the cartridges themselves proved quite effective on large North American game.

The introduction of the .338 Winchester Magnum ushered in the day of the modern .33 caliber medium bore rifle. Suddenly a wide variety of good .338" diameter bullets were available to reloaders and wildcatters. The various .33-06 wildcats, including the .333 OKH, immediately became obsolete as wildcatters started substituting .338" bullets for the old .333" bullets.

The .338-06 was born and that wildcat was eventually domesticated by A-Square. A-Square offers factory loaded ammunition for the .338-06, and Weatherby offers production rifles in the caliber.

The .333 OKH is now obsolete, a historical curiosity. Anyone with a .333 OKH rifle who can find a supply of .333" bullets can still use it to bag a wide variety of North American game, of course. .338-06 reloading data can be used, as other than the slight difference in bullet diameter, the two cartridges are functionally identical.

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Copyright 2005, 2012 by Chuck Hawks. All rights reserved.