I have a 3 groove 8 twist pacnor 223 ai. It shoots well but if given a choice I lean towards 5r. Some say 3 grooves hold up longer with less fire cracking etc but I've seen 3 grooves become hard on jackets pretty early. I think the wider lands get a little rough and start chewing up jackets. I've known some guys that used to run fast twist 3 groove Lilja's but found they were poofing thin skined bullets early on. I think you'd be fine either way with a 223.
Bb
