next project is a 338-06 on a persian mauser (CZ 98/29) action. Any problems with feeding in this combo? What is the benifit to the improved version?

I have thought about this caliber and 8mm/06 also. I took a 3006 casing and seated an 150 gr 8mm bullet into it, then tested it through my VZ 24- No problems. Only tried one, too.
Of course, things may be different with a 250 gr 338.

Your results may differ.

CAL9

Rob-airto,

The 338-06 is a FUN cartridge! Mine is an AI version and requires fireforming. There is a very small amount of velocity increase with the improved version but not enough to be able to tell at practical hunting distances. I just like the looks of the sharp shoulder on the improved one.
Mine is on a CZ550 action so I can't say if there would be any feeding problems..but I wouldn't think there would be any and if there were then they should be simple to resolve.
I like the recoil with the 250's. Recoil isn't one of my favorite things, but this one has just enough that it feels like you've unleashed something with significant power when you touch one off.
That's about all I can tell you at this point because I'm just starting to play with mine...I imagine you'll get plenty of feedback, though!

Good Hunting,

I have one that I've been using for two hunting seasons now. Mine was built on a german Mauser 98 action. Reloading is quite easy and I have no feeding problems. I've been using 200gr Nosler BT's in mine. I know the cartridge can handle heavier bullets for the whitetails down here the BT stops them in their tracks.

If you go with the standard version, the .338-06, now called ".338-06 A-Square," you can use stamped factory cases should you want to do so in the future.

Weatherby loads ammo for it, and their .338-06 cases are sold by Cabela's and others. You can always use .30-06 cases or .35 Whelen cases for your .338-06, and use the ".338-06 stamped" cases in those instances when you don't want to mix different types of ammo. I believe that for hunting in Africa the stamp on the cases must match the rifle.

I used the 338-06 std. and Imp. for a number of years and I liked it...But discovered the .338 Win would do everything the wildcat could do and a whole lot more with the same felt recoil, so I switched, a move I have never regretted....both work on a std. 98 action just fine.