I started using SR primers in .38 Special back in the late 1960s. At that time I had a co-worker who was a top-level Bullseye competitor who used a .38 Colt OMT revolver in the CF stage. He mentioned to me that he used SR primers in his .38 Special WC competition loads as he found after considerable testing that they were more consistent, at least for him. I thought it was heresy at the time, as everyone knows that SR primers are for rifles only, not handguns, but he was right.