can you use a hornaday 300 aac bullet seating die for 308 win

Of course you can as long as you have enough adjustment range for the coal you want. Buy a universal seating die and never worry again.
If it’s the custom line hornady and not the match line then their 30 cal seater is a universal, from 300bo to 300wm are the same. It’s why I hate it in my coax for black out.