Powder Choices for SPs

[djtjr]

Guys what is the conventional wisdom on powder choices for SPs? Say vs a standard rifle in the same cambering does cutting down the barrel necessitate going to a faster burning powder to create efficiency or maintain as high a velocity as possible?

i am about to start load development on 2 SPs

First 6.5 WSM (leopard) and second a 260 rem. both will be using either the 130 or 140 Berger or the 140 amax. in my rifles chambered for the WSM using the same bullets i am using H-1000 and in the 260 am using H-4350. would these still be good choices for an sp with a barrel thats 10-12 inches shorter than the rifles.

anyone have any recommended loads for these chamberings in a SP?

thanks in advance,
Don

 

[dirtball]

The only first hand experience I have is with a 7mm WSM, have a F-Open rifle with a 31" barrel.
Built an SP using a Stiller action and a 21" barrel, same chamber reamer.
Took it to the range and started with same load as the rifle, RL-25 and 180gr JLK.
That load produced 3080 FPS in the rifle, but only gave me 2675 in the SP.
Went to 4831SC in the SP and was able to work up to 2900FPS, no pressure problem and one finger bolt lift, with the 180JLK in a 21" barrel and with AMAZING accuracy.
Took 5 Antelope with it in Wyoming last year between 500 and 780 yds.

Dave

 

[yorke-1]

I would try some slightly faster powders.

When I was working up loads for the 338/375 Ruger out of an 18" barreled Striker, I started with H4831SC. My velocities were disappointing (around 2500fps with a 225gr TTSX) and the muzzle flash was like a flame thrower. I switched to RL 17 (similar burn rate to IMR 4350) and now I'm getting over 2900fps with a 225gr bullet. I had similar results with the 250gr SMK using H4831 (2450fps) and H4350 (2650fps)

The slightly fast powders have just worked a little better for me.

Andrew

 

[Ernie]

I use H-1000 on two 6.5 Leopard SP's with 130 Berger's.
Work great for me.