This is what i am currently doing with all the batches i've been making recently. I may not do it though with a batch that is very "off" because it may cause more inconsistency from grain to grain.
I did some more testing with the sharps today on this fantastic day off, im liking the standard deviation alot, i only recorded the last 3 shots unfortunately but its very promising.
By weight, 65 grains of this new batch of 1.5F gives 1242 fps average with a 543 grain bullet with 1:20 tin alloy in a "535gr" bullet mold from CBE. It has about 0.100 compression because the volume this 65 occupies is about 75 grains on the volumetric scale.
The accuracy at 50 yards is about 1 inch from 6 shots prone but i still have alot to learn about reloading BPC for precision and also shooting. I typically get 0.3 MOA with my .308 from a bench but shooting a 540 monster bullet at 1240 fps in a 34 inch barrel and iron sights is not the same as a 168 gr bullet going at 2700 fps in a 24 inch barrel with high power scope...i have alot to learn about trigger pull and consistency from shot to shot.
Attachment 293796
Attachment 293797
From Mike venturino's book he got 1230 fps with 73 grains by weight and 530 gr Postell bullet so i think this charge is close to being "it" for this bullet. No joke, it sure kicks.
Attachment 293798