Well, I had a chance to try out my reloads last weekend and today. I was pleasantly surprised how well the .308 billets worked in the SKS bore. I was even more surprised, despite seeing the phenomenon many times, of how dramatic a very small change in charge can have on group size.
My original loads were .5 grain steps starting at 20.3 grains and going to 22.3 grains. I shot these on Sunday and found the 21.3 loads to be the best, so I loaded some more at 21.0, 21.3, and 21.5 grains and shot them at No. Leominster today at the 100 yard range.
I started with a box of Brown Bear crap steel case stuff to compare, which I shot during my lunch hour at Harvard today. One note -- for the 124 grain stuff, which I originally used to sight in the Techsights, I had to use the 0-2 aperture. When shooting the 150 grain .308's, I had to use the 300 meter aperture, or the hits were off the paper with a 6 o clock hold. Using the 300m though made them slightly high:
11 rounds of Brown Bear:
the 21 grain loads:
The "accuracy" load -- 21.3 grains. It doesn't show too well, but there's a 3 round group just above the 10 ring on the left. This was 10 rounds, not sure where number 10 went.
And then, this is what blows me away, up just 2 tenths of a grain, and the group goes to hell. 21.5 grains: