357 mag 125 JHP: True Blue? WSF?

Hello,

I’m looking for a low end 357 load.

The components I have available are:
1. Zero 125 JHP
2. True Blue or WSF
3. Once fired PMC 357 cases

I have the following manuals: Speer, Lyman, Lee.
I didn’t see anything for WSF.

For True Blue: Lee and the Ramshop website are recommending a min of 10.4 for a Hornady 125 XTP.
Lyman has a min of 9.4 for a Hornady 125 JHP.

I noticed True Blue 38+P loads are in the range of roughly 6 to 7.

Googling the net doesn’t show a lot of interest in WSF for 357. True Blue get’s mentioned much more often.

Any experience, suggestions or just general feedback for True Blue and 357?

I’d like to go under the min loads if possible, down to about a 38+P level load.

The load would be used in: S&W 60/65/686 and a Marlin 1894(18.5" barrel)

Thanks,
Don.

 

Western Powders data is your friend.

http://www.accuratepowder.com/wp-content/uploads/2010/09/WP_LoadSpec_7-2-13.pdf

This is where I would start.

 

First pick a powder, any powder, as long as it is mentioned in a good loading manual or three. Something I have used for years is; take the Max. 38 Special +P load data for the powder from a good manual, and multiply it by 1.05. (+5%) That will take into account the extra capacity of the 357 magnum brass, and give about a +P load, with a little "extra". Depending upon your powder choice, Magnum primers will probably not be necessary.

If that works, and you'd like something a little warmer, multiply the Max. +P load by 1.10, (+10%) which will give you about a 38-44 load, or +P+ pressure/velocity, (Really hot .38 Specials, or maybe a "mild magnum" load!) either of which should be entirely safe in a 357 magnum.

Or...just use the starting load listed in the manual under 357 magnum. I am overcautious, so I try to choose powders that are bulky enough so a double charge will be readily seen during post-powder/pre-bullet inspection.

Have fun!

 

Hello IWAC,

Funny thing I ended up doing just about what you suggested.

After a little more research I had ended up with the following two True Blue loads:
1. 7.7 grains/125 JHP
2. 9.5 grains/125 JHP

The 7.7 grain load is basically a 38+P load +10%. The 9.5 grain was a little below Lee and Ramshot 357 mins but a hair above the Lyman 357 min.

The 9.5 load was somewhat “357-like”; although not as much kick as some PMC 125 JHP factory stuff I brought.

The 7.7 load was fairly light. Especially in the Marlin.

I wish I’d brought some factory 38+P for comparison. Next time.

It would be nice to have chrono data. Maybe for Christmas….