Big Diff Between 158 and 160 Keith's?

[doc540]

I realize different loads need to be tested, but some may already have experience and advice when reloading .357 with Win231 and going up to a Keith-style 160 grn SWC, 16 BRN.

Any significant difference from my 158 grn loads with 6.0 of Win231?

Or should I load them the same and test from my 158 base data?

thanks

Goal is steel silhouettes at 50yds.

[Bill Steele]

The weight difference is obviously not going to make a big difference. A bigger factor for pressure is the bullet profile and specifically the length of the bearing surface, that is, the part that rides in the lands and grooves. A longer bearing surface means more pressure.

I always use start loads and work up when switching to a new bullet. I would think you will be fine to use 158gr load data of the same bullet construction for a 160gr bullet, just use start levels and work up for the new profile.

[Cowboy T]

Ideally the alloy would be softer than 16 Brinell, but as long as it's wide enough for your gun's chamber and bore, and lubed properly for the application, it should work great. My own cast boolits can vary up to 2 grains, depending on the specific cavity in the mould. Like Bill said, it's no big deal. Also, how deeply you seat the new projectile will be a factor, and that can and often does depend on the bullet's profile.

Checking the book, the load range for .357 is listed as 6.2gr to 6.7gr, so you ought to be fine at 6.0gr. .38 Spl loads go from 4.0 to 4.5gr, with .38 +P showing 4.7gr.

[Cowboy T]

Ideally the alloy would be softer than 16 Brinell, but as long as it's wide enough for your gun's chamber and bore, and lubed properly for the application, it should work great. My own cast boolits can vary up to 2 grains, depending on the specific cavity in the mould. Like Bill said, it's no big deal. Also, how deeply you seat the new projectile will be a factor, and that can and often does depend on the bullet's profile.

Checking the book, the load range for .357 is listed as 6.2gr to 6.7gr, so you ought to be fine at 6.0gr. .38 Spl loads go from 4.0 to 4.5gr, with .38 +P showing 4.7gr.

[doc540]

Thanks

I've been reloading with a Redding powder measure that has the rifle diaphragm, but I've ordered the correct pistol diaphragm so maybe my throws will be more precise.

That should help my groups at 50yds.

[doc540]

Thanks

I've been reloading with a Redding powder measure that has the rifle diaphragm, but I've ordered the correct pistol diaphragm so maybe my throws will be more precise.

That should help my groups at 50yds.