I have both a 35 Whelen and .35 Whelen AI. Both are fine cartridges but loaded to equal pressures there is very little gain to be had from the AI version. And, depending on the rifle, you may lose magazine capacity due to the increaed shoulder diameter. you may also experience feeding difficulty. The feeding can be sorted out but it can be an issue to be contended with and is often overlooked by those wanting to AI an existing rifle.
I agree to stick with the std Whelen or go 9,3x62. I have all three and for max performance would pick the 9,3x62. I like the two Whelens I have because one is all weather the other open sights only.
Of course, if you HAVE to have an AI, I'd opt for the 40� version as dies are typically less, fireforming much easier, and it is more common which would help resale if that is a consideration.
My 40� Ai was just as accurate when fireforming as it was with fireformed cases. I simply fired my standard 35 Whelen load in teh AI chamber and presto, Fireformed cases and sub MOA groups all at the same time.
