ArchAngelCD
Member.
I'm looking at the Hodgdon load data site and I was wondering why there is such a difference in velocities between the 30-06 and 338-06 with the same bullet weight and powder. I can't understand why the 338-06 can deliver higher velocities than in the 30-06 with the same weight bullet and same powder. After all, they are the same exact case with a blown out neck.
Example:
30-06 / 180gr SIE SPBT / IMR 4064 / 2700 fps / 58,200 PSI
338-06 / 180gr NOS BT / IMR 4064 / 2920 fps / 61,600 PSI
30-06 / 200gr SPR SP / IMR 4064 / 2469 fps / 57,400 PSI
338-06 / 200gr HDY SP / IMR 4064 / 2729 fps / 61,800 PSI
30-06 / 200gr SPR SP / IMR 4007 SSC / 2497 fps / 57,800 PSI
338-06 / 200gr HDY SP / IMR 4007 SSC / 2729 fps / 63,000 PSI
Other than the fact the pressures are higher in the 338-06 rounds I can't figure it out. The difference in pressures don't seem like it would be enough to generate that much more velocity. Also, why are the the pressures in the 338-06 higher than the 30-06? I'm thinking of putting a 338 in my rifle line and I'm not sure if I should go with the 338-06 or the 338 Win Mag. (cost and availability of ammo are not a factor since I reload my own ammo) The performance of the 338-06 is fairly close to that of the 338 Win Mag with much less powder and form what I've read less felt recoil. I do know velocity is surprisingly higher in the 338-06 than the 30-06 with the same weight bullet although they are wider. I'm a little confused here...
Example:
30-06 / 180gr SIE SPBT / IMR 4064 / 2700 fps / 58,200 PSI
338-06 / 180gr NOS BT / IMR 4064 / 2920 fps / 61,600 PSI
30-06 / 200gr SPR SP / IMR 4064 / 2469 fps / 57,400 PSI
338-06 / 200gr HDY SP / IMR 4064 / 2729 fps / 61,800 PSI
30-06 / 200gr SPR SP / IMR 4007 SSC / 2497 fps / 57,800 PSI
338-06 / 200gr HDY SP / IMR 4007 SSC / 2729 fps / 63,000 PSI
Other than the fact the pressures are higher in the 338-06 rounds I can't figure it out. The difference in pressures don't seem like it would be enough to generate that much more velocity. Also, why are the the pressures in the 338-06 higher than the 30-06? I'm thinking of putting a 338 in my rifle line and I'm not sure if I should go with the 338-06 or the 338 Win Mag. (cost and availability of ammo are not a factor since I reload my own ammo) The performance of the 338-06 is fairly close to that of the 338 Win Mag with much less powder and form what I've read less felt recoil. I do know velocity is surprisingly higher in the 338-06 than the 30-06 with the same weight bullet although they are wider. I'm a little confused here...