Best high velocity .357 powder using standard primers.

[rooster59]

AA#9, IMR4227, and Alliant's 2400, in no particular order. All are very good. My fav is AA#9, meters real nice.

 

[SHR970]

Close AA#7 There AA#9.

 

[Waywatcher]

Alliant 2400.

Next question.

But seriously, in my 4" GP100, I load a 158 hardcast LSWC with 14.0 grains for 1244 fps with an ES of only 38fps, or a 180 hardcast with 12.0 grains for 1149 fps with an ES of only 30fps. Both loads were developed using CCI 500 and are near-max or max loads, depending on source. I stopped moving up because they were accurate and developed the velocity and consistency I wanted, with no pressure signs.

 

[oldfortyfiveauto]

I've had some success in my Ruger 77-357 with Vihtavouri N110. They don't say to use magnum primers and I did not. I still need to crony the load, but it appears pretty warm.