Dirtfarmer,
My range results were interesting today. The load was the Tipped 30-grain Varmageddon in Winchester brass, already fire-formed in this rifle, with CCI 450 primers and three charges of 300 MP:
14.0 grains--3270 fps, .77 inch group
14.2 grains--3287 fps, 1.49 inch group
14.5 grains--3348 fps, 2.48 inch group
As the powder charge increased, the groups started stringing more and more vertically. Looks like 14.0 grains is it, but out of curiosity I resized the cases from the 14.5 grain load and seated some primers. The pockets were still quite tight, and Hornet cases are notorious for expanding pockets with hotter loads, because there's so little brass around the pocket.
The barrel on this Brno is 58cm (@22.8") long.
