I've owned a bunch a SA Rugers over the years and still own 6. They all had issues with the base pin coming out with heavy loads, greatly affecting accuracy. Check the cylinder play, both front to back and side to side with the hammer down. Be sure your Micro Sights are tight, too. I'd also measure each chamber throat and the forcing cone. I'd then shoot one cylinder at 5, 10, 15, and 20 yards to see whazzzup. Then call Ruger.