I'm using a Ruger stainless 77 sporter with laminated wood stock in 223. After breaking in the barrel, bedding and trigger job I'm averaging 5/8" for the last 7 three shot groups I have fired at 100yds. My tightest group so far has been .225". Ruger barrel quality seems to have improved considerably over the last few years. I like the 223 especially with Sierra 50gr Blitzkings, very explosive! If you go with the 223 give Hodgon's Benchmark a try. Great clean burning powder which meters beautifully and gives good velocity. I'm getting 3350fps with the 50gr Blitzking out of a 22" barrel.