55 gr is working so well in my Axis that I'm not considering further experimentation. I shoot either factory Hornady V-Max or a Nosler Varmageddon hp hand load I've worked up. As they say...."if i do my part" I get half inch 5-shot groups at 100 yards with either.

I might add that it was imperative for me to find a good 55 gr round for the Axis since my other 223 is a Mini-14 (181 series) with 1:10 twist. The Mini thrives on 55 gr, so it's nice to have a load that shoots well in either gun.