[rumlover]

All,

Took 50 rounds of 220 SMKs loaded with 8.3 grains of AA9 to the range and put them over the chrony. The powder weights were thrown by an RCBS chargemaster/scale combo. I had velocity variations from 968 to 1160fps. Wiskey Tango Foxtrot?

Is there another powder that is more consistent? I imagine the difference in veolcity with AA9 is in the fraction variations (ie 8.357 grains v/s 8.321 grains) but our scales can measure past the 1/10th of a grain.

Is 1680 more tolerant?

Is there another powder that is better suited?

Because I know someone will ask:
8.5" Pacnor barrel
1/8 twist
7.62SD

The good news, however....I was getting good groups when the velocity was under a 20fps standard deviation. Consistently 3/4" groups at 100y.