The 223 AI is an awesome round ,but for an autoloader i thnk you would be limiting yourself unless you were shooting the rifle as single shot.
A friend took a varminter praire dogg'in and said he had a blast ,if the first shot was off he could adjust and send another round within seconds -made some 450yd shots !
Stick w/what you got and shoot the crap out of it ,when you need another barrel you might try to go up to a 6mm-223 or down in caliber to a 20 'practical'.223 brass necked down to 20cal -very simple and the short range ballistics are great.
Good luck --Mike
