38spl and 357mag using the same components-ish ?

M

Metal god

New member
I feel a little silly asking this but I do believe there is no dumb question in reloading so here it goes . :o

I was just getting ready to start loading some 158gr LRNFP using HS-6 , Fed 357 brass and CCI SP-magnum primers . This cartridge/caliber is new to me FWIW .

So I look up the 357 data there's not a lot but then I think oh I can use 38spl data to . I look that up and I find pretty much the same components in 38spl as I did in 357 . The two major differences is the 357 load uses magnum primers and much more powder .

This is the first time loading a cartridge that actually can be loaded two different ways

I think , well you always start low and work your way up . Lets start with the 38spl data and start to write my note . I keep a data note with everything the current load is using including the powder increments . So there I am writing all the data down then I start with the increments , 5.0 ,5.2 , 5.4 , 5,6 , 5,8 and then I think , didn't I just see the 357mag load start at like 9gr ? Why am I starting at 5gr then and I stop ?

I'm there wrapping my head around this confusion . OK I'm not using 38spl brass or the recommended standard primers recommended for 38spl but also don't want to load full power 357mag loads . I should add I never plan to use 38spl brass ever regardless of the load ( Moose farts all the way to full throated 357magnum loads )

That said :confused: what am I loading here ? lol -- I keep thinking If the powder and bullets are the same in both 38spl & 357mag data . my powder charge range is actually from the 38spl low to the 357mag high . Is that accurate ?

Meaning the 38 data is 4.8gr to 6.4gr and the 357 data is 9.0gr to 10.2gr . Is my actual load spectrum 4.8gr to 10.2gr ? If so there's no way I'm working this load up from low to high unless my increments are one full grain jumps until I get somewhere in the 8gr area ???

FWIW this is for a GP-100 6"
 
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357 load uses magnum primers and much more powder .
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Consequently you are also loading to higher pressures, and velocities.

This is the first time loading a cartridge that actually can be loaded two different ways
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The components certainly are often exactly the same. However, you are loading to two VERY different Cartridge specs. 38 Spc loads are all under 17,000 psi; 357 go up to 35,000. That is why they are designated as 2 different cartridges

Although 38 can be fired in a 357, same as 44 Spc can be fired in 44 Mag. But 357 cannot be fired in a 38: they wont fit in the cylinder, and , if they did, they may well damage 38 revolvers. Revolvers are specifically built for their intended cartridges. A 357 must stand up to firing full load 357 rounds.

Two different cartridges
Two different SAAMI specs
Many different S&W "frames" (K, N, Model 10, etc)
 
Yep thanks for the reminder although that was understood . I probably should have lead with I'm loading for a 357 magnum revolver ( GP-100 ) . The 38 cases shooting in a 357 but 357's not being able to shoot in a 38spl is one of the reason I only want to use 357 brass . Another is the fouling and carbon build up in the cylinder when using 38 brass that then can interferer with loading 357 brass later .

For me it just seems simpler if I stick to 357 brass only regardless of the pressures loaded to .

Does less bullet jump help with accuracy in revolvers ?
 
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Yes you really do have that big of a loading window. Though i would mention that HS-6 does better in this cartridge using magnum primers (even in 38 special) and burns cleaner at the higher pressures.
There’s not much of a difference in accuracy due to bullet jump between 38 and 357 in the same gun. Some yes, but nothing you will notice at 25 yards. Farther out, then yes.


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Just stick with .357 data, HS-6 buns pretty dirty at lower pressure but once you hit the sweet spot it's nice and clean and works very well. It's also a fairly forgiving powder to use as far as pressure spikes.
 
Not to mention that using .38 SPL load data in the longer .357Mag case will lower the pressure even more. With HS-6 that isn't good.

Start at midrange .357 mag data for HS6 and work up from there.
 
With light loads the slightly larger .357 case will have even less pressure than a .38 Special case and .38 minimum loads will be even dirtier. It's typically recommended to start .1 or .2 higher when using the larger case.

Primer choice is more a function of the powder being used vs the cartridge.

The jump from a .38 case vs .357 is inconsequential. The jump from the cylinder throat through the forcing cone and into the rifling is larger and the same either way.
 
MetalGod: Run 357Mag/158-160gr-LRNFP/8.5 - 9.5gr HS-6/MagPrimer and call it a day.
Being a relatively fast powder, do not exceed 10.0 (IMHO - diminishing returns for Max pressure. 8.5gr is where you reach 100% burn/6" barrel)**

If you ever run across Vitavhouri N-110, grab it.
Best powder there is for well-behaved Mid-Mag loadouts in 357-44Mag


**
Besides, it's a nice round number. ;)

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Metal god,

The answer to your question hinges on powder space below the bullet. In QuickLOAD I get between 5.2 and 5.3 grains in the 357 Mag giving you the same peak pressure as 4.8 grains does in the 38 Special if you use the same crimp groove on the bullet with both cases. Because the 357 Mag case is 0.135" longer than the 38 Special case, if you use the same crimp groove for both, the bullet is 0.135" deeper into the 38 Special case, making the powder space smaller. That's why it takes less powder to achieve the same peak pressure in the shorter case. Some 0.357" diameter bullets have two crimp grooves or two cannelures for this reason. The one nearer the base is for 38 Special and the one nearer the nose is for 357 Mag. If your bullet is one of those, then the same load would work for both.
 
mehavey said:
8.5gr is where you reach 100% burn/6" barrel)**
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Thanks that's good info , assuming that's true ;) I feel I really started this thread out on the wrong foot by not stating the question was for 357 revolvers only and that there is this huge gap between 38spl max charge and 357 min charge . What I should have asked was , is that max 6.4gr 38spl to the min 9.0 gr 357 zone ok to load in because that's likely where I want to be ? As always you guys have brought it around to what I really wanted to know anyways .

What I'm now looking at doing is starting in the 7gr area and stopping somewhere just below 9gr ????

Thanks UN . I've seen the double crimp grove bullets but did not put that together .
 
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I think I'll start with the primers. With HS-6 (which I have extensive experience), I prefer to use CCI 550 mag primers any time I'm loading for revolver. Revolver cases are cavernous and HS-6 is tough to ignite. So I run a mag primer with 38 or 357. (Side note: Semi-auto cases are more confining, so I believe a mag primer is unnecessary with HS-6.) That said, my experience with HS-6 in 38 Special was underwhelming. Which makes the primer choice moot (for me).

I think the difference in load data charge weight - aside from the case size, as detailed by Unclenick - is that there is a big difference, performance-wise, between 38 and 357. And that's the biggest reason between the differences in charge weight.

You don't want to use 38 cases in your 357 firearm, and I can understand your logic. That train has left the station. Fair enough.

That said what am I loading here?
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What are you loading? It sounds to me like you're not so interested in 357 mag performance as you are to just make some quality economical (lead bullet) range ammo, assembled in a 357 Mag case. Let me know if I missed the mark here.

I don't know what a "LRDFP" is. But I'm going to assume it's a lead bullet.

Here's my personal experience with lead 158's and HS-6 (mag primer): I ran 'em up to 8.2 grains, moving along at 1145 f/s through a 4" bbl. At this charge level, leading was getting extensive, yet the propellant was still running sooty. Moving to a plated bullet, I couldn't get the HS-6 to run happy and clean until I got up to about 8.6 grains - way beyond a lead slug's ability to not smear itself all thorough the barrel and cylinder throats (for me). Leading was quite manageable at 7.6 grains (1036 f/s, 4" bbl), but powder fouling - soot, unsent propellant everywhere - was atrocious.

Conclusion: YMMV, but for me, this project was a bust. To salvage my efforts, I did a work up to 9.0gn with a plated SWC; and it was a good round, but I noticed some plating breakdown and copper fouling. So I move it to a jacketed HP bullet. Runs a nice crispy 1175 f/s (4" bbl) in a well-behaved package with minimal report and recoil - a fine round. I Found it particularly well suited for my 3" 686, where it runs 1115 f/s. Makes for fun days at the range; and would certainly do the job in a SD situation.
 
Metal god, the 1st rounds I'd ever loaded were 357mag lite. That was back around 1980 and used in my S&W Model 19. I was using store bought Speer 158gr. LSWC and Speer 148gr. LWC loaded over Bullseye powder and CCI 500 primers. The Info data I started with was from a Speer #10 manual and worked very nicely. I still have that Speer manual too.
 
Nick_C_S said:
I don't know what a "LRDFP" is
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Sorry should read LRNFP ( lead round nose flat point )

Your HS-6 and lead experience is a little discouraging . I was really hoping this combo was going to be perfect . I can always go to HP38/231 for the lead bullets . I have several hundred 125gr XTP's coming next week that the HS-6 should work well with . What I don't want to do is add another powder to my inventory . I use HS-6 and HP-38/231 in both 9mm and 45acp along with a few others . I really don't need a new powder to work with . I'll tell you what though . I have 2+lbs of CFE-pistol that I did not like in 45asp or 9mm . Maybe these 158gr LRNFP 357 loads are just the thing for that powder ??? I also have some 180gr XTP's coming I'll load with H-110 and or 2400 .

I'm still going to try the lead with HS-6 and hope I wont be disappointed . My charge increments are now likely as follows . 7.0 , 7.4 , 7.8 , 8.2 , 8.4 , 8.6 .
 
I'm still going to try the lead with HS-6 and hope I wont be disappointed.
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Please do. We read about others' experience; then we create our own. So we'll wanna know how it works for you. HS-6 runs cool; and that bodes well for lead. If you don't mind the weak burn (low pressure, soot, etc.), they'll likely go downrange with good accuracy and minimal leading (if you don't drive 'em too hard).

I have several hundred 125gr XTP's coming next week that the HS-6 should work well with.
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Heh, more bad news :p. Well, kinda. I've run those tests too. I've taken HS-6 to 11.2 grains (11.3 is Speer #14 max) using Speer's 125's - not exactly the same bullet. They were good potent rounds - make no mistake. But Standard Deviations were high; as I had some trouble getting them to settle down. And by "some trouble," I mean, "wasn't able to" :D. Extreme Spreads were consistently in the 110 f/s neighborhood with 10-round samples. This, and other load work ups lead me to the conclusion that without a doubt, HS-6 likes heavy bullets like no other propellant. Pick a caliber; HS-6 performs most consistently pushing the heavies - across the board.

Side note: Hornady's 125 XTP's are awesome (all weights and calibers, actually); and I've done some work ups with them (have 400 waiting to be loaded), but not a lot. But I've never loaded 125 XTP's with HS-6; due to the high SD's with other 125's. I have loaded 158 XTP's with HS-6, and they're fine performers; again, the heavy bullet thing. I like heavy bullets, btw. So I have more experience with 158 XTP's (have 800 in inventory to be loaded).

What I don't want to do is add another powder to my inventory.
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Preaching to the choir. I'm currently drawing down my propellant selection. Trying to get down to five or so; from a high of 13. That said, have you tried Power Pistol? Yeah, Power Pistol is the . . . stuff. Makes bullets go fast. Runs clean. High energy. Ignites easily (no mag primer). My favorite intermediate burn rate propellant; and the only one I intend to keep in my inventory. Just sayin'. Oh, and makes smokin' 125's.
 
That 7.0gr/HS-6/357case/158gr-LRNFP/1.590" drops things to 38Special Pressures (95% burn)

Probably good plinking load.


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I am just starting with reloading and as long as you have something to shoot at, this is honestly the best caliber to learn to reload... 38 spl out of a 357 gun just leaves you so much margin for error...
 
If you don't mind the weak burn (low pressure, soot, etc.)
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I'm assuming you wrote that while remembering my thread stating I HATE sooty cases :( . I really do , It bothers me way more the it should for sure . I was just looking at the power pistol data . It does not seem to do much more then HP-38/231 , am I seeing the data correctly on that . I'm saying this in hopes that I can just use 231 and have some pretty clean burning loads .

The more I look around the more it seems the profile of a lead bullet really effects the powder charge . I see many of the same weight bullets or very close with wildly different powder charges . Much more the you tend to see with jacketed bullets with the same weight . Is it anything more then what appears to be the bearing surfaces being so different from one another ?
 
That 7.0gr/HS-6/357case/158gr-LRNFP/1.590" drops things to 38Special Pressures (95% burn)

Probably good plinking load.
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Bullet on the right came from a 7.0gr HS-6 158gr bullet load from a .38 Special case at 945fps from a 2.5 inch barreled Model 19. Same load, or with a few tenths of a grain more powder, will do equally well in a .357 Magnum case. Also, with magnum handgun loads the powder used determines whether to use a magnum primer. In the case of HS-6, always use a magnum primer whether you are using a .357 or .38 case.

Don
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Metal god said:
The more I look around the more it seems the profile of a lead bullet really effects the powder charge . I see many of the same weight bullets or very close with wildly different powder charges . Much more the you tend to see with jacketed bullets with the same weight . Is it anything more then what appears to be the bearing surfaces being so different from one another ?
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Lead bullets do seem to have a wider variety of shapes. We've got everything from hollowbase wadcutters to the standard lead round nose. The amount of bullet seated in the case can vary significantly even when they have similar weights. I've got a 140 grain SWC that has a short front driving band and tiny nose and when seated correctly has as much of bullet seated in the case as a normal 168 grain SWC. That's a huge difference in weight but the pressure is going to be pretty similar and using he wrong data for the 140 grain bullet could cause problems.

To add to the confusion the reloading manuals seem to be less consistent on where the loads start and stop. Lead bullets are much less likely to stick in the bore and starting loads can be quite a bit lower than jacketed bullets, however the loads usually start pretty close to the jacketed range. Sometimes the loads go really light but usually not. On the opposite end of the spectrum lead load data can sometime be artificially limited because of fears of leading with too high of velocity. This is why having multiple manuals can be a big help.
 
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