Well I thought I had my new load figured out, until today. Two weeks ago I worked up to 60 gr of 4831sc with the 180 Bergers, 5 shots varied only 4 fps, and averaged 2942 fps. I loaded several rounds exactly the same and hit the range this A.M. just to double check. My shots, in a fouled barrel, measured 2848, 2864, 2896, 2900, 2902 (after cooling the barrel for 13 minutes), 2896, and 2904. All the shots were fired at least 2 minutes apart. The weather today was 68 deg and sunny. Due to the bad mirage I couldn't tell which shots impacted where but all were within 2.5" and three were .58", all were shot at 300 yds. Any Ideas as to why the huge velocity difference?