Today I tested several bullet weights including 150's, 165's, 180's and 220 grain with the Hybrid 100V powder in my 300wsm. I am impressed with the results in velocities. I got the highest chrono'd velocities of any powder I've tested with all of these bullets. Two of the groups were at 1" and the other two were in the 2" splits. It's been awhile since I've done much shooting and even with shooting rest, I'm probably partly to blame for the bigger groups. I'll be trying different bullets in the future to tighten up those groups. I stayed within the loading data limits and found no pressure signs. Hodgdon claims higher velocities with this powder and I found it to be true but the differences were only 50-100 fps better than previously tested powders. Anyway, I'll be testing it for temperatures to see if it's finicky between hot and cold. I refridgerate one set of matching loads and leave the other set at outside temperature on the front porch on a day above 70 degrees before I shoot them. Chronographs tell the story from there. Generally if my velocities vary much, so do my groups. Places I hunt can be frozen in the morning and 65-70 degrees in the afternoon so that is quite a split to deal with. Maybe just splitting hairs with all of this but that is what reloading is all about.
I have also tested Ramshot Big Game and Magnum powders and wasn't impressed with the pressures, velocities and barrel fouling. I stayed within published load values and found high pressures and low velocities with those powders, not to mention it was filthy. I'm sure other people may have had good experiences with Ramshot powders, but that was my personal experience. To each his own.