Hey Collateral,
FWIW, here's some recent data I came up with using a Winchester 115g RN and Universal Clays. Thought it might help the cause:
November 22, 2007 - 38 degrees F. 1.125" OAL. Glock 34 Winchester SP primers.
Grains Avg Vel ES PF
4.6 1138 51 130.8
4.7 1149 47 132.1
4.8 1173 40 134.8
4.9 1189 42 136.7
5.0 1209 65 139.0
I have found 4.8g w/ a 115 to be an easy-shooting, slightly stout, but very accurate load. Even with your shorter barrel, you should have no problem making minor with this load.
Also, Universal Clays seems to work best at pressure. In other words, I wouldn't recommend it for light loads or you start to see sooty cases, the velocity spread gets erratic, and with it, the accuracy. As you increase the powder slowly, you will see all these factors start to come together to optimum. As you see from my numbers, the lowest Extreme Spread comes at 4.8, which appropriately produced the most accurate round.
As one of the readers suggested, you might consider buying even a cheap chrono. It's a great tool when working up a new round.
Good luck!
BigDad
