I finally got a new lot of RL26 and I wanted to try WLRM primers in my 280AI. I wanted to change over to them because the barrel is short and I often hunt in the cold- sometimes extreme cold. So I first loaded up a ladder with the new batch all with the WLRM. Went to the range and fired them and when I got to 2905FPS I shot the next 1/2 grain up, light ejector marks, so I came home and pulled the higher charges. I reloaded 4 with BR2 primers and 4 with WLRM, same charge, same seating depth. HUGE jump, which I have been reading has been successful for some people. Went back to the range and shot all over the chrono. The crazy thing is my AVG MV was exactly the same over both strings at 2886. My SD and ES were a bit better with the WLRM, BUT my group size shrank from nearly 2MOA with the BR2 to just over .5MOA with the WLRM. I’m like, whoa, is this even possible? I’m still kind of in disbelief and wondering if there is something wrong with my mount, or my action screw. How can group size shrink that much when MV stays the same, the only difference being primer?