My SD and Extreme Spread numbers are bad and I'm wondering where to start looking for ways to get these numbers lower. The purpose of this load is revolver target shooting and plinking at ranges of up to 350 yards. At 25 yards, I get outstanding groups, but today's chrono numbers make me wonder how much of the 350-yard performance is me and how much is the difference between individual cartridgers in the cylinder. Here are the technical details:
Equipment: Hornady LNL-AP; large powder measure rotor.
Bullet: Speer Gold Dot 240-grain bullet
Brass: Remington nickel plated brass, brand new, never fired
Primer: CCI - LP - Magnum
OAL range: 1.606-1.615
Charge: Hodgdon H110 powder = 23.6 grains (+/- 0.1 grain)
Crimp: Very strong crimp - any more and I'd buckle the cases
I tested this load with two revolvers:
Colt Anaconda 6-inch results:
Average Vel 1300
SD = 23
ES = 68
Smith & Wesson 29-3 (Silhouette model) with a 10.5-inch barrel:
Average Vel = 1410
SD = 47
ES = 128
This load was worked up from lower charges until 25-yard accuracy was satisfactory, but now I shoot at much longer distances and I'm worried about inconsistencies that may have been negligible at only 25 yards.
What's a good place to start if I want to reduce the SD and ES numbers to a more respectable range?
Equipment: Hornady LNL-AP; large powder measure rotor.
Bullet: Speer Gold Dot 240-grain bullet
Brass: Remington nickel plated brass, brand new, never fired
Primer: CCI - LP - Magnum
OAL range: 1.606-1.615
Charge: Hodgdon H110 powder = 23.6 grains (+/- 0.1 grain)
Crimp: Very strong crimp - any more and I'd buckle the cases
I tested this load with two revolvers:
Colt Anaconda 6-inch results:
Average Vel 1300
SD = 23
ES = 68
Smith & Wesson 29-3 (Silhouette model) with a 10.5-inch barrel:
Average Vel = 1410
SD = 47
ES = 128
This load was worked up from lower charges until 25-yard accuracy was satisfactory, but now I shoot at much longer distances and I'm worried about inconsistencies that may have been negligible at only 25 yards.
What's a good place to start if I want to reduce the SD and ES numbers to a more respectable range?