Re: .223AI with 75 AMax....... What powder though ???
I'd like to help you, and I will but first chide you a bit:
1) This properly should have been posted in the reloading section.
2) You posted so you have access to a computer, so use Google, it is your friend, and type in .223 AI loads, you be amazed at what info you can find in less than 5 minutes of searching.
3) We have a Sniper Hide Reloading Depot as a depository for all sorts of data, found here:
Snipers Hide Reloading Depot
4) And finally, any of the better slower burning powder used for the .223 also work well with the 223 AI like, Varget, RL15, 4064, 4320, 4895.
5) I don't do pet loads, as what works for my rifle, might not work for you. You sorta gotta find it yourself. But I'd start with a mid charge weight range Varget load listed for a regular .223 and work your way up.....
Bob