Based on what Rich has indicated in previous posts, the AI case has ~ 6% more capacity than the standard -06, and his Sherman case is another 5% more spacious.
It sounds like you are pushing the AI a little faster than what I saw him post as he at one point also chambered the AI, but based on everything I have read, i would guess ~ 100fps gain over the AI.
My rifle will initially be set up as straight 6.5-06.
But it is only a matter of time until I build another in the Sherman chamber or ream this one out....If it is really accurate, I will not be able to bring myself to ream it out.
Good reason to build another