Help with 357 Mag - Powder & Primer Questions

IrishPsych

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I think I'm over thinking this but need help on 357 mag loads.

I'm a long time reloader but haven't done 38sp or 357 mag.

Bro inlaw has a SW 327 TRR8 and we're all going camping. So I naturally got 2k 158gr SNS Casting hi-tek to make 1k of 38sp and 1k 357 mag.

Powders I have: bullseye, titegroup, clays, 231, lil gun, sport pistol. These will work for 38sp for plinking rounds. Will any of these powders give a decent 357 mag experience with 1000 velocity?

I can't find locally any slower powders at stores. I can trade for blue dot, 296, or Herco.

I dont have small mag primers.

Can I substitute small rifle for small pistol mag? Is it worth/safe doing that for 600 rounds?

Many of the manuals differ on loads for 357 mag. I've seen 6.5gr of bullseye reportedly at 1300fps which I would never expect. Supposedly from Alliant data and a 158gr lead swc too.
 
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Not sure what data source you have maybe you are confusing powders, but from the Alliant site:
357 Magnum 158 gr Speer LSWC Speer 1.57" CCI 500 Bullseye 4.8 939fps

W231 will get you safely to 1000fps in a 357mag case. From the hodgdon site, 158gr LSWC:
Winchester 231 .358" 1.610" 5.0 1,109fps 23,900 CUP

You could go up to 6.5gr of W231 without bending anything. They show 6.9gr under a 158gr XTP as max.
 
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You can also get a bit over 1000 ft/sec with Sport Pistol, according to Alliant's web data.

I know some folks load Lil Gun for 357 Mag for max loads, but I don't use it as I have read that it burns very hot and has a bad reputation for barrel erosion at the cylinder gap and top strap cutting. No personal experience with it though. Plus I don't think it would be an appropriate load for a coated bullet either; you would probably have leading issues since it burns so hot and gives very high muzzle velocities.
 
Uh... Better check that "report"...!

I think I'm over thinking this but need help on 357 mag loads.

'm a long time reloader but haven't done 38sp or 357

Many of the manuals differ on loads for 357 mag. I've seen 6.5gr of bullseye reportedly at 1300fps which I would never expect. Supposedly from Alliant data and a 158gr lead swc too.

As fredj338 indicated, Alliant's MAX for that 158gr is less than 5gr Bullseye.

A 30% increase is a disaster waiting to happen, IMHO.:eek: Where did THAT come from?

WIN 231 & Clays are both on the afformentioned Hodgdons site.

Good luck & STAY SAFE!
 
The powders you listed in burn rate from fastest to slowest, Clays, Bullseye, Titegroup, Sport Pistol, 231, LilGun.
LilGun is rated a slower burner than 2400, much too slow.
I'd do the 231, as talked about in post #3.
 
I would suggest W231/HP-38 for the .38 Special and W296/H110 for full power .357 Magnum ammo. Since you have no magnum primers and want to keep the magnum rounds to less that full power I suggest 2400 or AA#9 instead.
 
I have been using 5.5 grans of 231 under my hard cast 158 grain SWCs for decades.

Standard primers work just fine

That will put you right around 1000 FPS in that 5" 327 TRR8 Smith & Wesson

trr8-2s.jpg
 
If you can't get Unique, I suggest Herco. Lyman's current manual has loads for your needs using Herco.

For 1,000 FPS and 158 gr SWC in 357 Magnum cases, I reach for Unique using 6.0 grs.
 
Here's some real chronographed data from my S&W 4" 27-2 that you
can use for loads in the 1,000+ fps range. 357 brass with a SPM or SR
primer as they give virtually identical velocities in the .357 case. All with
a 158 gr cast SWC
5.2 grs Titegroup = 1027 fps
5.6 grs " = 1060 fps
5.3 grs Bullseye = 1012 fps
5.7 grs " = 1057 fps
5.8 grs 231 = 1061 fps
 
38 special ...Target Loads , great for tin cans & paper targets .
Your 158 gr. lead SWC over 2.7 grains Bullseye ...it's a magical load !
Use standard primers .
When loading one style/type bullet ... I suggest
Load 38 special loads in 38 cases and load 357 magnum loads in 357 cases , much easier to tell them apart .
Some will say load 38 special loads in 357 magnum cases but I don't agree if you are loading the same bullet in both .
Gary
 
With the powders that I have on hand, I only need the cci, Win or federal standard pistol primers for my loads to work, since 2400 is the slowest powder that I use for the Magnum.

With a 158gr Lwc bullet in my 686 6" my faster powders will get;
Bullseye............... 921
Green Dot ........... 1281
BE86 .................. 1271
HS-6 .................. 1108 (target)
Unique ................ 1320

I save the w231 for the 38 special loads.
 
Only vetted sources for data should be used. That is powder company or bullet companies, never internet sites. Typos are rampant as are just misguided reloaders posting things. Stick to vetted sources for your starting data.
I agree 100%. I have my Rule #1; I pay no attention to any load data I see on any forum, pet loads website or magazine article. Also disregard any load data I hear from any gun counter clerk, good intended friend, range rat, or gun shop guru. I get most of my load data from published reloading manuals and a few from powder manufacturer's or bullet manufacturer's web sites. I started reloading with the data supplied with my Lee Loader (1969) and ignored Bubba's load suggestions or the current shooting celebrity's data. In all the time since I have had one squib and no Kabooms...
 
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I guess that's where you and I differ a bit, mikld. I will listen to other load data, including data off the web, range rat, etc, but I also back it up with published load data from a reputable source such as a powder company, bullet maker or loading book. And if their range rat data falls within published load data I might give it a try out. But I will make sure such load data is valid and not overpressured before trying it out. I also haven't kaboomed a gun either in 50+ years of reloading.
 
With the powders that I have on hand, I only need the cci, Win or federal standard pistol primers for my loads to work, since 2400 is the slowest powder that I use for the Magnum.

With a 158gr Lwc bullet in my 686 6" my faster powders will get;
Bullseye............... 921
Green Dot ........... 1281
BE86 .................. 1271
HS-6 .................. 1108 (target)
Unique ................ 1320


Nevada Ed...aka "Hotrod" Ed"....pretty fast velocities, I use 2400 for those GD, BE86 and Unique speeds you're showing!
 

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