Mike, how can you tell whether the RSM is a tack driver or not when it is getting your attention every time you light one off? I know I couldn't when I started shooting mine. I was getting tenderized in the beginning until everything settled in and I was getting used to it. I actually got 1", 5 shot groups with Federal ammo when I finally made up my mind that all that pounding was fun. I know now that it don't hurt that bad at all, the Lott is now the king of hurt for the moment.