Not long ago I picked up a rifle and RCBS full length die for this,but would like to know How to fireform the cases,Powder,load,bullet.Also anyone have one?I always liked the 35 Whelen,and would expect this to be quite a round.

The Brown Whelen actually moves the shoulder forward, so your best bet would be to expand the case neck on .35 Whelen brass to 9.3mm or .375, whichever TAPERED expander you can most easily attain, and then run them into the full length sizing die until the bolt handle will just close on the formed cases.

Another option is to purchase 30-06 cylinder brass and simply run it into your sizing die until it will chamber in your rifle. This brass is a straight walled 30-06 casing with no neck of any kind. Although it is rather expensive if would probably give you the best brass with the least hassle. You would want to make sure the brass was the proper length after any of these forming procedures before loading and firing. This brass is headstamped .35 Whelen and is available at http://www.z-hat.com/Cylinder.htm
These cases would totally eliminate fireforming. Run them through the die and start developing loads instead of spending the time and components on fireforming. In that light, the premium price doesn't seem quite as steep.

I shoot a .35 Whelen Imp, which gives up a bit of powder capacity to your version of the cartridge. If you have the chance after you get some brass formed, I'd be interested to know the difference in capacity, in grains of water, between the standard Whelen and the Brown/Whelen.

Good luck with your new project.