Took a couple of my recent loads out yesterday. Shot from my G-20 with 6" KKM barrel, new Starline Brass, Winchester large primers and 180 gr. Bayou Bullets. All loaded to 1.255".
8.2 grains BE-86
Average Velocity - 1289
Spread - 61
SD - 22.92
7.7 grains Winchester Auto Comp
Average Velocity - 1197
Spread - 35
SD - 15.84
No pressure signs with either load.
The Auto Comp load was max load according to Hodgdon, just loaded a little longer. I found this to be a very nice target load. Very light recoil and little muzzle flip. It came in almost exactly at the velocity Hodgdon lists. I was using a 6" barrel and they test with a 5". I'll try 1.25" OAL next time and see what difference that makes.
The BE-86 load was impressive. Again, loaded to book max (for JHP), but a little longer. With the 6" barrel, this load exceeded the books veocity by a bit. I will likely load some a little lighter and see how low I can go and still stay above 1200fps.
Didn't get to this time out, but I also plan to run these through my stock G20 barrel.
Yes those 6" barrels tend to bring out the extra velocity not seen with the 4.00" - 5.00" barrels.
Thanks for your range reports. :D