Put some starting loads together with 73gr H870 and Hornady 140 SST's virgin win brass was used and WLR mag primers seated to clear the magwell of my FN action 26" bbl. First go around chronoed a 2700 fps reading with a measurement of .517 just forward of the belt with a begining reading of .509 second string of 73.5 gr read 2736fps third at 74.0gr was 2738fps 4th at 74.5 showed 2752fps and 5th and sixth did not read, seventh string at 76.0gr came up at 2836fps with the same .517 ahead of the belt and a fairly flat primer but no cratering. I fired off some factory Winchester 140gr .264 win mag fodder and they show an average of 2798fps with identical flat primers and a .517 ahead of the belt with an initial reading of .509 as well. seems like it takes a full 2 grns of powder increments to observe a meaningful gain. I would like to get at least 3100 fps but will take at least 2grs more to realize this. I did not record groups as my mounting system failed me with not enough windage adjustment. What's with the low velocities as compared to the reloading manuals higher readings?

When I still had H870 I believe I was getting 3220 FPS out of a 74gr charge & a 25.5" barrel. I'd have to double check my records though