Blue Dot, Steel, or 2400 for .357 Magnum?

With 158g bullets I think you will find blue dot and aa9 will work well at the velocity you are seeking. Blue dot at about 1 to 1 and a half grains under max has been the most accurate powder for 158g bullets in my 6 inch barreled 357 revolvers

I prefer milder magnum loads when shooting my SA Blackhawk with 6.5" barrel. I normally use 7.4 grains of Unique under a 158 gr. bullet.

For my .357 magnum lever action rifle, I like hotter loads. 14.5 grains of 2400 under a 158 gr. XTP JHP or 14.2 grains of AA#9 under a 158 gr. XTP JHP shoot very accurately.

12-12.5 of 2400 is my target 357 load. It has just the right amount of recoil I want and very accurate.

In the past, 12.1-12.3 gr. of 2400 has done well with 158 gr. SWC with my revolvers. Quite the manageable magnum (lite) round. I tried them out in the rifle. I got lube fouling after shooting about a 10 rds. I'm going to kick it up a grain or two and see if that will be better.

For mid-range loads in 357 or 44 magnums, I really like BE86.

HS6 with magnum primers or 2400 and Unique with standard primers. The latter 2 in my hand guns. HS6 in my carbine. Unique is great all around powder for lots of calibers from 38 to 45-70.

I'm not sure I quite understand why you wouldn't want to use Magnum Primers for the heavier loads.

Click to expand...

Magnum primers are for use with harder to ignite ball powders and in loads that will be shot in extremely cold weather. Flake powders ignite easily and standard primers are all that is needed. The extra burn of the magnum primer produce higher pressure at lower load levels with powders like 2400 that can result in over pressure loads with the substitution of the mag primer. Read the current Speer manuals that warn not to use magnum primers with 2400 loads in their manual for .357 magnum.