.357Mag

PeterPan

CGN Ultra frequent flyer
Rating - 100%
26   0   0
Guys,
I am loading for SW 686 with 6" bbl and I wonder what is your favorite powder for 158gr SWC from Excel?

I am using 14.4 of H110 behind Win SP.

Thanks
 
357 loads

PeterPan said:
Guys,
I am loading for SW 686 with 6" bbl and I wonder what is your favorite powder for 158gr SWC from Excel?

I am using 14.4 of H110 behind Win SP.

Thanks
I was using an old S&W, just marked, 357 MAGNUM, before they went to model numbers. The 168 gr cast bullet was a bit long in 357 brass, so had to seat the bullet deeper and crimp on the top groove. 14 grs of H110 gave one five shot aqverage of 1329 fps, and only 19 fps spread from lowest (1320) to highest (1339).
Loaded in 38 Special brass, 13 grains of 2400 gave 1247 av. and es of only
28. With the 168 gr. cast bullet, 15 of H110 seemed a bit high on pressure, but seemed OK with 157 gr gascheck, in my gun.
With 5.2 grains of Winchester 231 powder and the 168 gr bullet, a 10 shot group had a high of 1026 and a low of 953. Use extreme caution when using a fast powder like this, where a double charge would easily go into the case and turn your gun into a hand grenade! In short, I think a good load can be developed for a particular gun, with either H110 or #2400. The 2400 is the faster burning powder of the two.
 
Last edited:
357 mag

It has been my experience with H110 and Win 296, with high velocity loads and cast bullets, as the number of rounds gets higher the worse the accuracy becomes. As a rule these powders are too hot and the burn time too long to be used effectively with cast bullets. Lead builds up in the bore from melting the back end off the slug.(unless a gas check is used) Cooler burn powders like H4227, 2400 and IMR4227 will give similar velocity without the melt effect. Hard cast bullets with some of the high pressure lubes will sometimes allow more high velocity rounds before the leading appears and the accuracy suffers. Also some barrels seem to lead up quicker than others.
Carry on!
 
Back
Top Bottom