The biggest 22cal I ever tinkered with was a 22-284, your 22-300AYE is well beyond that. I would suggest trying the 55gr NBT it seemed to hold up the best to extreme velocity. For powder I was using H1000 and VVN170, you might have to try something like H50BMG.
In the end it wont matter for too long that barrel will be toast after a couple hundred rounds(probably sooner). It is very close to the infamous Eargensplitzen Loudenboomer !!!!!!!!!!!!! I believe that was a 22-378 Weatherby
boatanchor,thanks for the info. I may pick up some of the 55's to try also as I can use the extras in other rifles I have.
H1000 is what I have on hand, years ago one of the RCBS guys also mentioned one of the 50BMG's.
