IMR 4320 was the best overall powder in my former 338-06. 23" w long throat. 225's did 2670 + 1/2 MOA.

4064 and 200 NBTs is a killer deer load. 2910mv and 1/2 MOA.

Here's a thread...

http://forums.outdoorsdirectory.com/showthread.php/92858-338-06-2700fps