I have been running my new 5R in .223 for about two weeks now. I have a Nikon Buckmaster 6-18 sitting on a weaver Picatinny base and Millett tactical bases. I have less than 500 rounds through it and she is dumping three shotters in less than a quarter inch at 100 yards. The five shotters are up around the .7" range. I'm using the Sierra 60 grain varmiteer with 22.8 grains of AA 2460. It's a keeper. I shot the groups below on Saturday. The conditions were ideal with no wind. The only limitation was the big loose nut behind the scope. This one is a keeper. It is a sweet little caliber that I can shoot all day long without taking a beating.