Today I finally shot some handloads through the Mega I made up with 115 grain Sierra Match Kings driven by Alliant Reloder 10x.
The first four 5 shot groups were pretty poor, averaging 2" or so. The last group fired (using 28.8 grains) went into 3/4" and showed absolutely no signs of over pressure. They were moving along at a little over 2600 fps average.
I'll make up some more right around this level, likely at 29.0 and 29.2 to try to beat the 28.8 result.
