To do a correct AI in a rimless case the barrel should be set back so that the headspace is a crush fit on the regular 7-57 before its fireformed. What with that rifles unique stock and perhaps sight ramp its not practical. The barrel will no longer fit the stock.
On the other hand it might work to rechamber it to 280 R. or the Nosler 280 AI.
Here is my other comment about AI's.
The AI's I had done in rimmed, rimless and belted rounds turned out to be nothing but a hobby extension. Overall they complicate things and are a waste of time and money.
I had a Sears M51 (High Standard made 30-06 on the FN action) barrel set back to 30-06 AI. It works ok but now I don't even use the rifle and I would have to look for ammo. It must be here somewhere!
The 30-06 worked superb. Suppose the AI works too.
Now I can understand the want to have something new. I did it and you should be able to also if you want to.
