I use 35 Whelan brass with a little bump left at the shoulder to make a crush-fit when I close the bolt. Main thing is too low pressure splits cases at the shoulder (can't explain why) so I never load less than the book's max load for a particular bullet and powder. You will automatically lose some pressure due to the larger chamber so going light backfires (pardon the pun). Also, for some reason these fireforming loads are universally accurate, sometimes better than I can acheive with that bullet/powder combination in the formed cases.

1. 338-06

2. 338-06 improved

3. 338-06 ackley improved

4. 338-06 A Squared

5. 338-06 rcbs



Is the 338-06 improved, same as ackley improved with the 40 degree shoulder and deminsions.



Is the 338-06 A squared same as plain 338-06?



I see the 338-06 RCBS is different.



Im planning a 338-06 and like the improved with the 40 degree shoulder.



I saw the diagrams on steves page . But under reloading data he has only 338-06 A squared



Can someone fill me in and clarify all the 338-06 ,and improved deminsions/variations.



I see Reeding has 338-06 ackley improved dies. Anyone with a 338-06 ackley , What dies do you use ? Or just 338-06 neck die set?



Thanks Rick

The A-Square & .338-06 are one in the same. I shoot a .338-06, a great caliber for NA hunting. I'm not sure of the diff. w/ the RCBS & Ackley versions, but there are no flys on the std. version. The 210grNP @ 2750fps is a perfect allround load. Any good 250gr soft @ 2450fps is good in the timber or out ot 250yds or so.

The ackley has alittle larger case diameter at the shoulder and 40 degrees. The rcbs has i think 25ish degrees.

Im going to build a 338-06 on a m720 action and am thinking why not a ackley with the steeper shoulder and alittle more capacity. Is it true a Ackley case with the 40 degree shoulder will last and reload more times with less case stretch?

Case Life? Maybe but not enough to matter in the big picture. I think it matters more in thin cases like the Hornet or 30-30.
FWIW, I get about 100 fps more in my 338-06 AI in a Sauer 200. It is a single stack magazine so feeding is no problem. If I were to do it again on a standard 30-06 action I would probably go with the standard 338-06 just so feeding stayed slick as possible. That's based on my experiences with the 6MM AI, 280 AI and the 375 H&H AI.

1. 338-06
2. 338-06 improved
3. 338-06 ackley improved
4. 338-06 A Squared
5. 338-06 rcbs
6. .338 Sabi

You can add the Sabi to the list, but I don't know its dimensions. The .338 Sabi is the African version of the .338-06, and you should be able to find it in the Internet. Of all those above, the .338-06 (A-Square) benefits from headstamped brass. I imagine that brass is also produced for the Sabi, but I am not sure.