Got to shoot a Ruger SR556 last Saturday. Recoil was smooth and pleasant, the narrow railed hand guard felt nice in the hand. However when I field stripped it, I found metal shavings under the rear take down pin all the way up under the bolt catch. Bolt carrier tilt was shaving metal from the buffer tube. While shooting the Ruger rifle was nice, it looks like they have not worked out all the kinks yet.