Acc to Tom Turpin (?)

The .333 OKH was based upon a .30-06 case necked up to a .33 caliber bullet, and the .334 OKH used a shortened .375 H&H case necked down for the same bullet. The .338 Winchester Magnum also used a shortened and blown-out .375 H&H case, necked down to accept a .338 caliber bullet.