I have not read all the responses. But I had a similar problem when I picked a 375 Whelen AI. It was what the reamer rental place had and the die retailer had. So I went AI.
The problem is the controlled round feed of the Mauser requires a bit of work on the rails and feeding ramp.
I also have a 280 AI on a 700 action. With that action there was no need to alter the feed.
