Exactly what is the difference between the 333-OKH and today's 338-06? I know that ballistically they are equivelent, but I'm talking case demintions here.

The .333 OKH used an actual bullet diameter of .333, not .338. There may be other differences, but I'm not immediatly aware of them.

Except for diameter they are the same. Loading data is the same. Bullet cost for the 333 is much higher. Woodleigh makes a 333 bullet at about a buck a piece, occasionally a box of Barnes originals shows up, they were two diameter, the rear third took the rifling and the front section rode the lands. Then there is the 344-OKH, a belted case like the 338 Mag.

Cartridges of the World says that apart from the bullet diameter, there was no difference at all and that loading data for both can be used interchangeably. There was another similar grand old cartridge that is regrettably dead today, the .318 Westley Richards, but we who live in the back of beyond, in India, occasionally get to see some of the older veterans from time to time.

Difference: .005" in bullet diameter. Due to availabilityu of bullets, if the boys were designing this round today, it would be a .338 O.K.H.!! If one had a loose chamber neck, one could probably fire .338/'06 ammo in a .333 O.K.H., if the case necks expanded enough to release the bullet sufficiently. (AM NOT RECOMMENDING THIS!!)