Help: 357 mag loads

[pdog]

I have a new Ruger GP100 6 inch 357 mag and just bought 500 Cast Performance 158 grain SWC bullets. I would like to get a load worked up for the 357 mag, (not the slower 38) and have not loaded cast bullets before. I have Unique & HP38 pistol powders on hand but will get whatever you recommend for a fast load to kill coyotes with that I call in. I have loaded regular bullets since 1974 but never cast ones so not sure whether I can increase or need to reduce powder charges for cast loads as compared to copper jacketed loads. Also, what is max without gas checks on these commercial bullets I bought? Thanks a ton!!!!

[James C. Snodgrass]

Welcome aboard PDOG . You can use jacketed data with the cast bullets. As to the max speed of the bullet it will depend upon many factors . You won't be able to reach max with either of the powders you listed . I myself have pushed cast out of my GP to over 1600 fps with out any leading issues with a heavier boolit and H-110 . But I wold give the Unique the first try as it is the most versatile powder around . James

[UweJ]

hello pdog
sorry as I don´t have any of your powders but
6.4grains of Bullseye -1217 fps no leading-
7.2grains N330 - 1195 fps no leading
both loads with 158gr.SWC no GC
Uwe

[HeavyMetal]

Get a manual and check loads using WW 296, Alaint 2400, and H-110.

These days 296 and H110 are supposed to be the same stuff (?) but still follow the Manuals for data and don't switch info.

Not a fan of 2400 in pistol loads but thats just me. I might also suggeast the 4227 twins as well. They don't make the same power levels as the 296 loads but are much more consistant in very cold weather.

I also have a preference for 150 grain boolits in the 357 instead of the heavier stuff. I can get a flatter trajectory with the lighter faster boolit that will still carry good power to 75 yards, which I think is to long a shot on any animal with a 357.

Lets talk boolits. Not sure what diameter your store boughts are but I bet they are good and hard! Hard is not a bad thing, generally, but they may be a bit on the "skinny" side.

If you have a way to "mic" them see what they are. should be at least .358 but if you didn't make a specific request they may be .357 and leading may or may not be an issue.

I have been told that the GP100 has a cylinder long enough to use the 358429 boolit. I have this mold in an HP design. I am not a boolit seller, to much like work, but if you would like a handfull to try out PM me and I will get some to you.

[EDK]

Get the newer BASIC RELOADING MANUAL from HODGDON...it covers HODGDON, IMR and WINCHESTER powders. The Cowboy loads are a good LOW starting point and go on up from there.

I like the lower end loads around !000 feet per second in 357 OR 44...shoot 40 rounds daily when I can. HP-38 and TITEGROUP are my current favorites. UNIQUE or 2400 are the classic powders for magnums. H-110/WW 296 are the velocity champs, but have a narrow usability range. LIL' GUN is also popular. I prefer to use boolits that will also feed in my MARLIN Cowboy rifles in 357 (and 44,) but the round nose/flat point has a lot of virtues in a revolver also.

Try and find a "sweet spot" between accuracy, power and controllability. The higher end stuff can be unpleasant because of noise, muzzle blast and recoil. Your 6 inch barrel is the right choice for your purposes and still easy to carry in the field.

:Fire::cbpour::redneck:

PS There's a bunch of "the wild cousins" that den somewhere down hill from my house. They make a fair amount of noise around dusk and the wife's dogs go crazy responding from the back porch. If the back yard wasn't fenced, I'd probably have a couple less dogs. The "cousins" get pretty close at night, but I like to hear them sing. A round or two from some grouch across the canyon will usually end the serenade.

[Lutzy48]

EDK,

I am curious as to what primer you like with 2400. I was recently working up an accuracy load for my Ruger Vaquero and Marlin Cowboy. I got low on WPSM primers and had to start over with standard WSP primers. The result was the standard primers did not seem to provide as much consistency as the magnum primers with 2400.

[EDK]

I used WSP for everything until the recent shortages...bought some CCI to keep up my inventory until things calm down.

I had some issues with unburned grains of powder with 2400, so I went to IMR 4227 and 5744 for the limited amount of "rifle specific" ammo I load. "Generic ammo" is set up for the VAQUEROS/BLACKHAWKS, but usable in the rifles, and the pistol powders like TITEGROUP or HP-38 are economical and clean burning. I am going to try 2400 and LIL GUN in the future...various posts have suggested a heavier crimp/case neck tension would address the problems I had previously.

There's a lot of information here and on other reloading forums. It's a d*** poor day that I don't learn something new...and I've been reloading since 1968.

:Fire::castmine::redneck:

[outdoorfan]

I have a new Ruger GP100 6 inch 357 mag and just bought 500 Cast Performance 158 grain SWC bullets. I would like to get a load worked up for the 357 mag, (not the slower 38) and have not loaded cast bullets before. I have Unique & HP38 pistol powders on hand but will get whatever you recommend for a fast load to kill coyotes with that I call in. I have loaded regular bullets since 1974 but never cast ones so not sure whether I can increase or need to reduce powder charges for cast loads as compared to copper jacketed loads. Also, what is max without gas checks on these commercial bullets I bought? Thanks a ton!!!!


I use 7.5 grains of Unique behind a 140 grain swc in my 4-inch 686. They move out the muzzle at 1200 fps. I would try anywhere from 6-7.5 grains to find out what your wheel gun likes.

7.5 grains is probably on the high end for that 158 grain boolit.

[Lutzy48]

The cast boolit gods are with me! The local shop had small pistol magnum primers yesterday. Now I am back in business.

[MT Gianni]

If you have a good grouping jacketed load worked up in the same weight as your boolits, try a 10% reduction and work up to it. It may be near the speed you need. Start with the simple before you change everything.

[Papa smurf]

Hi pdog Try 6 grs. Unique. I have a Blackhawk and a Taurus. My son has a GP100. All three guns like this load---- +/- 1100f/s ----- Good Shooting-------Papa Smurf