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JakeB
01-06-2010, 06:26 PM
Load Request - .357 Magnum 170gr LSWC "Keith"

I'm looking for load data for a 4" S&W using a 170gr Keith style 170gr LSWC.

I don't have and 'Magnum' powder yet but have been looking at purchasing some 2400, H110, or Lil Gun for this load.

I would like to start somewhat below max load and work up from there...so H110 concerns me a little.

Thanks,

Jake

versifier
01-06-2010, 06:58 PM
...I would like to start somewhat below max load and work up from there...so H110 concerns me a little...

Welcome to The Guide Jake.

That whole statement concerns me - more than a little. They call them Starting Loads for a good reason. That's where you begin load development with a new powder or bullet. Every time. And then you go up in charge in small increments watching for overpressure signs until you get the accuracy and/or velocity you had in mind, the fired brass still extracts easily, and the primers show no signs of flattening, cratering, or piercing. It's the difference between dying eventually of natural causes and going out early and spectacularly with a Darwin Award. You might get away with shortcuts a few times, but sooner or later Murphy's Law will kick in and the consequences will not be pleasant. There are too few of us now as it is to risk losing more by ignoring the basic safty rules.

What loading manuals do you have on hand now? Most of them should have data for 170-180gr bullets. Two current manuals are the bare minimum, three is better, and four or more is best. Consider them inexpensive life insurance. With most handgun loads, data for cast and jacketed is the same, so that's not an issue. You can always use jacketed data if that's all you've found, and also data for slighty heavier bullets without problems.

Powder selection is generally a matter of the gun's opinion, as is bullet choice. Not every revolver will shoot cast without some work on it, so if you are having accuracy problems, post and we will figure out why. I would be starting with 2400, Unique, or Blue Dot and magnum primers.

JakeB
01-06-2010, 07:21 PM
No need for concern Versifier,

I would be starting at STARTING LOADS however with H110 it is warned never to start below 3% of max...hence the reason for my statement in the OP.

As for manuals I've got about 4. Only one of them listing 2400 for this bullet weight. None of them listing Lil Gun.

Can you seriously use jacketed data for a cast lead load? I thought that wasn't safe also.

kg42
01-06-2010, 10:54 PM
I take 3% as a generic value as Hodgdon don't know what bullet you will use.

You have to consider the available space in your case with the bullet seated, then "When loading slow burning ball powders in reduced loads, NEVER load cases below 90% of capacity. Powders like H110 or W296 are prime examples of this condition. The reduced loads are harder to ignite by the primer, and sometimes NEVER ignite at all."
http://www.freedomarms.com/loading.html

Lil'Gun is getting an awfull reputation as a barrel throat killer, due to high nitroglycerine content/ heat; and Freedom Arms advise against it (I didn't find the info on their site).
It is however suspected that with a better ignition potential it would be more suited to reduced loads and cold weather, but at what price?
An other aspect of the problem is that today most guns are made of stainless steel which is pretty bad at conducing heat (http://www.schuemann.com/, info section)

About using jacketed data for a cast lead load, lead will usually offer much less resistance/friction, unless your bullets are very hard/ dry lubed/ oversized (in other words, commercial). Soft lead is also known to obturate very well and therefore raise pressures.
Of course in some applications (rifle, very high pressure calibers, short barrel twist), your lead bullet migh not be up to a jacketed's load.

kg

versifier
01-07-2010, 12:11 AM
Excellent. Better safe than sorry. We have a lot of newbys visiting here and if I get out the soap box and violin about it fairly often it's because I don't think it's worth taking any chances assuming that it's something everyone knows. Everyone ought to know it, but it only takes one mistake to trade in your guns for wings and a harp. When I see a new member post something that could be misinterpreted by an inexperienced loader, as moderator I have to err on the side of caution to be sure. ;)

Yes, it is perfectly safe to use jacketed data for most cast handgun loads (pistol and revolver cartridges). Pressures are lower and velocities are a bit higher than with a jacketed bullet of the same weight. Only when you are shooting hand cannons with medium and large capacity rifle cases do the rules change.

If you try the same thing with rifle cartridges you'll lead up your barrel pretty quick and be really sick of it. For them you need to learn about reduced loads with extruded and flake powders. I have experimented by pushing the cast velocity/pressure envelope beyond the strengths of lead alloys and watched a .5MOA rifle start having problems keeping 5 shots on a 4'x4' target board at 50yds within 10 shots.

Personally, like you I am very leery of any load with such a narrow charge weight range as H110 has in this application. If, for instance, you work up a load in chilly weather, and find good accuracy at or near MAX, what happens to the pressure levels when you're shooting it midsummer? Pressure spikes. Often over red line. Some powders are much more temperature sensitive than others, so a bit of caution is a healthy thing as far as I'm concerned.

Despite the fact that they meter well and many loaders love them, I have never been a big fan of spherical powders. I like the versatility of being able to use extruded powders in reduced loads without worrying about turning my guns into shrapnel and my face and hands into hamburger. When I started loading it was more a matter of convenience and limited space for powder storage. In the years since, though I have tried and used many different spherical powders and even keep several in stock for particular loads, they are never my first choices. You can't reduce them and you can't compress them safely, either. The ONLY one that I know from experience that is safe to reduce is 860, a surp powder for .50BMG that works very well for cast target loads in medium and large capacity rifle cases.

Here's data from Lyman for you:
.357mag, 170 cast SWC

BEYE 4.1-6.1MAX (light target loads)
Herco 5.6-7.1MAX
BDOT 8.3-10.0MAX (VERY temp sensitive, but still a favorite for great accuracy)
Enforcer 11.9-13.0MAX
AA#9 11.7-13.0MAX
2400 9.7-13.5MAX (Maybe the best all around if your revolver likes it)
N110 12.3-13.7MAX
H110 14.4-15.0MAX
IMR 4227 9.8-14.5 (compressed)MAX

runfiverun
01-08-2010, 08:24 PM
versifier that should be a sticky so it's read by all new guys here.
i see several loads i use with my 158 gr cast boolits listed there for the 170 gr.
the 357 is an okay caliber but if it needs more oomph i have a 357 max or a 44 or even the 445.
or the 450 express. and the list goes on.
i like the 2400 powder as it has a broad range and many uses,it even does well in rifle calibers with lead.