Can I safely load .357 brass to .38SPL velocities?

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Hi all,

I'm a reloading newbie. I recently picked up a progressive press and with it came a lot of .357 brass. I've been doing some reading while the rest of my gear arrives.

I'd like to start out loading .38s for my Ruger .357 magnum revolvers. I have some .38SPL brass, but I'm wondering if it is safe to load the .357 brass to .38 load specs? The previous owner has the press set for a light .38 using the .357 cases.

My powder is Alliant Bullseye, bullets are 158gr lead flat nose and Winchester SP primers. My Lyman manual (49th ed.) says 3.0 grains gives me 786fps in a .38SPL case. It provides no data for these same bullets in a .357 Magnum load. Should these 158 grain bullets NOT be loaded to .357 speeds & pressures? Or do I need another reloading manual?

I'm thinking of starting at 2.8 grains or so. I obviously want to be safe, but don't want squibs either. Is that too low?

I did some searching on the site and found:

38 +P in .38 brass - http://www.northeastshooters.com/vbulletin/showthread.php?t=38493&highlight=.38 . Indicates higher pressures are probably OK in .38 brass but not the reverse.

BostonShovel put a similar question here - http://www.northeastshooters.com/vbulletin/showthread.php?t=38493&highlight=.38 about .357 brass with SP primers and a .38 standard load however there was no resounding yes or no as to how safe it is.

And http://www.northeastshooters.com/vbulletin/showthread.php?t=15533&highlight=.38&page=2 - should I have gotten 147 grain bullets?

Do people generally feel that loading .357 cases to .38 specs is safe?

Thanks!
 
You are really doing nothing more than loading light 357 rounds. There is nothing wrong with doing that.
 
I would look specifically for light .357 loads if you really want them, rather than experimenting blindly.

But this begs the question, why don't you just load .38s?
 
I've been loading light .357 loads using .38 Special data for over 30 years with never a hint of a problem. In the .357 sections of some manuals, they'll even refer you to the .38 Special data for certain bullets, such as HBWCs.

If you fire large numbers of .38 Special (using .38 Special brass, that is) in a .357 you run the risk of building up a ring of fouling that will make it difficult or impossible to chamber .357 brass. I know that some claim this is an old wives' tale, but they can tell that to several guys I shoot with who have had this happen. You can eventually clean things out with a good brush and a lot of work, but why go through that when the problem is so easily avoided?

FYI, largely because I've got a couple 4-lb kegs of Red Dot that I'm trying to use up, my current .357 target load is 3.8 gr of Red Dot under a Speer 148 gr HBWC. Prior to that I was using 4.0 gr of Unique, for the same reason. Both loads work fine. .38 Special data typically gives a bit less velocity when loaded in .357 cases, but not enough to cause squibs. Obviously, you don't want to use .357 data in .38 Special.
 
Thanks for the replies so far.

Vellnueve, your suggestion for a light .357 is a good one.

I'd rather use the .357 cases because I have far more of them. I could buy more .38SPL cases, I supposed, but I'd like to use what I have on hand. As Dick pointed out and I've heard, running many .38s may cause a fouling ring. I figure if the revolver is chambered for .357 rounds, build .357s, albeit weaker ones if possible. Plus I would think I'd need to adjust dies if I'm moving between .38s and .357s to get the bullet seating and crimping correct as the .357 shell is longer. I could be wrong there, though. My press comes with .38 and .357 dies but they could just be two of the same ones. This way my only real adjustment is the amount of powder once I'm confident all is going well.

Thanks again!
 
Adam and Dick are absolutely correct - Dick even explained WHY. There's another reason why you don't want to load a lead 158gr bullet to .357 Magnum velocities - that's leading. If you plan to load hotter stuff, use jacketed or semijacketed bullets unless you like scrubbing lead from the bore. It shouldn't be as bad at .38 target load velocities, though.
 
Here you are: 158gr FNCM Gunhill. VihtaVuori N-32C/"Tin Star"- powder 4,5gr. 870fps. C.O.L. 1,58". Test barrel 6"
 
I use 3.8grs of Red Dot also but with 148gr dewc's in 357's and 38 specials.

One thing you really have to watch out for is, don't let a 38 slip in when your reloading 357's, because the end result will be a squib.

I know that for a fact..
 
It was a progressive and it was my fault for not having my cop installed on the press. Also I had not checked all the brass before hand, I just assumed that I had checked it in the past.

When I came back from the range I put the 38 back in to the press. I couldn't belive that the rotor looked like it went up like it should but if you looked at it real close you could see that it didn't complete it's cycle.

I weighed the charge and and it was 0grs. It taught me a good lesson.
 
It was a progressive and it was my fault for not having my cop installed on the press. Also I had not checked all the brass before hand, I just assumed that I had checked it in the past.

When I came back from the range I put the 38 back in to the press. I couldn't belive that the rotor looked like it went up like it should but if you looked at it real close you could see that it didn't complete it's cycle.

I weighed the charge and and it was 0grs. It taught me a good lesson.

Ah! I was having trouble figuring out what you meant as well, but I've got it now. That's good advice - I'm using a Hornady LnL AP and I try to look into each and every case to confirm that the powder is at the right level before I seat the bullet. Sometimes I can get a bit lazy about it, so your warning is a good one.
 
Now I see - since the case is shorter, it didn't engage the powder funnel and the shorter case didn't get filled. Good to know!
 
I use a Hornady LnL press also and while the powder measure is very accurate I have found some little problems with it.

One of the biggest problems is the arm on the powder measure becoming loose while your using it. The arm actually comes off the the screw that holds it in place.

This took me by surprise because it was tighten down and I never had a problem with it before. I was reloading 45's when I noticed that the rotor wasn't going all the way up.

It's happened more than once and now I check it about every 100 rounds and I really can't figure out why it would do that.
 
Don't load really light loads for heavy (158gr and up) jacketed bullets, or don't use .38 Special lead bullet data to load equivalently weighted jacketed bullets in .357 Magnum. You'll stick a bullet in the barrel.

Don't ask me how I know.
 
Here's what I've done so far - loaded 14 rounds of 158gr lead RNFPs with 2.9 grains of Bullseye.

I haven's shot any of them yet. The whole process took about 3 hours, including messing with the progressive and double and triple weighing powder and popping out each round to see that it got a primer, etc.

I'm having a few issues with my primers feeding, but I have a likely solution for that.

Thanks!
 
Don't load really light loads for heavy (158gr and up) jacketed bullets, or don't use .38 Special lead bullet data to load equivalently weighted jacketed bullets in .357 Magnum. You'll stick a bullet in the barrel.

Don't ask me how I know.

How do you know? [smile]
 
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