Herco in 357mag

[Poconolg]

I just want to check with the experts out there. I found a load for 357 using Herco and a 125gr bullet. The load was in a old manual. It had a starting load of 8.8 and max of 9.8 Would this load be correct? I plan on staring with 9gr and a magnum primer.

 

[tominboise]

As a cross check, Herco is similar to Unique but slightly slower burning. You can verify the max loads by comparing to Unique, if you want. I use Herco quite a bit and have had good luck with it. Although it doesn't meter in a measure all that well.

This is what I do. You shouldn't take advice off the Internet from random strangers.

 

[K22]

My Speer Manual, Number 8, 1970, contains loads for 125 grain jacket bullets and HERCO with a CCI Magnum Primer.

However, I am hesitant to post this data since it is over 50 years old. Powder formulations change and the load data in that time was more robust since there was less legalese in those days. Also, I have no experience with this powder.

I would try to find more recent published data from reputable sources however, if you PM me I will share that Speer data with you.

 

[Doug Casner]

Shot some in a .357 years ago. Pretty dirty. Mag primers might fix that. Doug

 

[kenhwind]

Alliant Powder 2004
125 JSP, Federal 200, Herco 9.8
Which is the same as your data.

 

[tommeboy]

You don't need the mag primer unless you use a ball powder. Save it for h110 loads

 

[Texas Solo]

Going back to the late 70's, I used 9.1 Herco & 125gr bullets in a S&W #27.
Shot great.

 

[dsinfour]

I used unique powder for the .357 and Her o in the 44mag