At the end of the day today at the range, I had five rounds left. Three were in Lake City M118 brass, and two were in Winchester M80 brass. All were loaded with Winchester primers, RE15 41 gr., and 175 Sierra Match Kings. The three upper left are the Lake City, the two lower right are the Winchester M80. Mix and matching brass manufacturers can affect your groups. 100 yards off a bipod. AR10T carbine, 16 in barrel.