Special loads in Magnum cases

[daverich4]

Is there any reason not to use 38 Special load data in 357 Magnum cases? I have a Model 60 that I've been shooting store bought 38's in to keep the wear down but I'd like to use my own loads in Magnum cases. Same question for 44 Special loads in Magnum cases for my 629 Mountain Gun. I've been using 7 grains of Trail Boss under a Lyman 429421 in Magnum cases but it's not the most accurate load I've ever shot and I'd like to try some Special loads to see if I could do a little better. Thanks.

 

[505Gibbs]

Is there any reason not to use 38 Special load data in 357 Magnum cases? I have a Model 60 that I've been shooting store bought 38's in to keep the wear down but I'd like to use my own loads in Magnum cases. Same question for 44 Special loads in Magnum cases for my 629 Mountain Gun. I've been using 7 grains of Trail Boss under a Lyman 429421 in Magnum cases but it's not the most accurate load I've ever shot and I'd like to try some Special loads to see if I could do a little better. Thanks.

What can happen is that the ignition of most of the powder can be an issue due to the increased internal volume for the same powder charge.
A possible solution is that after you load the cylinder up and close it - point the muzzle upwards with your finger off the trigger to settle the powder on the flash hole opening - then carefully bring it down to the horizontal for firing.

 

[daverich4]

Thanks for the reply. Unfortunately, when I practice with the Model 60 it's from a holster draw so I can't settle the powder as you suggest. I'm not worried about ultimate accuracy at that point as I'm shooting double action at a silhouette target. Do you there there's any particular danger in using the loads that way? That is, high pressure, low pressure, something like that?

 

[TAROMAN]

Because of the larger case volume, using 38 Special data in 357 cases will result in lower velocity and, possibly, erratic ignition.

Look in a good loading manual and you will see many "mid range" loads in the 357 section. Select one of these for your practice loads.

Even better would be to load with Trail Boss. Fills the case up well with powder puff loads. popular with the cowboy action crowd.

 

[tomf52]

For your intended use Bullseye is your friend. I don't think it can be position sensitive as I have loaded some very mild loads in .357 cases with it and never had a problem.

 

[riverrat38]

I load "light" magnum velocities for my M60. The Hodgdon site lists some in the 800 FPS range with Universal, and even less with Trail Boss and 231/HP38.
See:

Cartridge Loads - Hodgdon Reloading Data Center - data.hodgdon.com

With Trail Boss, use the Max load for best accuracy. I use copper plated bullets from Berry's, and it takes more pressure to get a good seal than with plain lead.
With fast powders like Bullseye, so little is used that I don't think there is much difference in percent of case fill between the .38 Spec and the .357 mag cases.
And, even if you use full magnum loads with fast or medium powders like Bullseye and Universal, the velocity is much less than with slow powders like AA#9. It is the velocity with a given bullet weight, and not the pressure, that causes wear and recoil.
I have read that some reloaders use .38 Special loads and add 10% to make up for the case volume difference, and this sounds about right, but others say that you need to stick with published data from the .357 magnum loadings.

rat

 

[TSQUARED]

You should not need to point the barrel of the gun up to settle Trail Boss powder which is v ery bulky and fills up the case fairly well. I have only used milder loads with Trail Boss powder and 158 gr. bullets in 357 Magnum cases. You have to do a boit of experimenting to detrmine which loads does best in your revolver.

 

[jepp2]

Yes you can do what you are asking. You will need to increase the charge and some powders may perform better.

Typically you need to increase your powder charge by 10% to generate the same pressure in a 357 Mag case as it would in a 38 Special case. Hodgdon Titegroup is another powder that isn't position sensitive.

I only load 357 mag cases for my 357 Magnums just to avoid having to clean the carbon ring that forms in the cylinder if you fire 38 special cases.

 

[Steve C]

There is no downside to using .38 spl data in the .357 mag case, just use data from the manuals. The difference in volume between the spl and the mag is quite minimal and if you are loading so light that the small difference will change velocity enough to stick a bullet you are below manufacturers published standard pressure .38 spl loads.

Generally when I load light in the .357 mag I use max load for standard pressure .38 spl data with 158gr lead bullets and find they shoot as well as any commercial .38's.

 

[pssman308]

I load 4 grains of unique in 357 cases with 158 grain swc it is comfortable to shoot and goes bang every time.

 

[john traveler]

The late, great Col Jeff Cooper once wrote about a .357 Python destroyed by firing what the shooter insisted was 2.7 grains Bullseye behind a 148 WC bullet loaded into .357 Magnum cases.

Investigation showed that it was not a double-charged case due to shooter error. It was speculated that the cause was secondary explosion effect from the minimal powder charge in the roomier case.

The conclusion from the good colonel was that he would not fire such loads in his guns.

 

[Jim F]

I`ve been shooting 5.0 grains of Reddot in 357 cases for quite a while-no ill effects so far. It is fairly mild. The Alliant Rep told me to try 6 grains but it is pretty snappy-more like a magnum load.

 

[Jim F]

The above load is with 125 grain JHP bullets and CCI 500 Primers in Winchester cases.

 

[jibjab]

"There is no downside to using .38 spl data in the .357 mag case, just use data from the manuals."

I agree, I start with upper end data for 38spl for low end .357 spl.

 

[daverich4]

Thanks for the link to the Hodgdon data and all the other suggestions. The Hodgdon is the one loading manual that I don't have. Because I load with an RCBS 2000 progressive press I think I might stay away from light loads of Trail Boss and give Bullseye or 231 a try just for consistency in metering. I use 7 grains of Trail Boss in my 44 Mag loads and the charge does jump around a little. Doesn't seem to make much difference @ 7 grains but it might @ the 3.2 grains suggested in the Hodgdon data. Thanks everyone for the help.

 

[sixshot]

Mid range loads using Bullseye, Unique, WST, AA #2 or 231 will work great in your 357 maggie, just follow your reloading manuals instructions & you'll find a sweet spot for your gun.

Dick

 

[johngalt]

I use 2.8 gr Bullseye + 148 gr HBWC in magnum cases all the time, works great.

 

[ArchAngelCD]

Like said above, there is no reason whatsoever not to shoot Special loads in a Magnum case. I usually shoot the Max .38 Special charge weight in the .357 Magnum case and those loads work well for me. The velocities will drop somewhat because of the additional case volume...

 

[BruceM]

Investigation showed that it was not a double-charged case due to shooter error. It was speculated that the cause was secondary explosion effect from the minimal powder charge in the roomier case.

That has been a consistent rumor going back to the days when the .38 Special was the hot ticket in a number of competitive shooting disciplines. The NRA technical staff, I believe, had H.P. White ballistics's lab investigate that and they were never able to duplicate the supposed "detonation" of light charges of Bullseye. I have never heard of anybody else being able to duplicate this under controlled lab type conditions with Bullseye either. This makes me extremely skeptical that this phenomenon actually exists.

Bruce

 

[K-framer]

The "SEE" effect has to do with light loads of SLOW powders.....in large case volumes. This phenomenon normally is seen only in rifles, but certainly CAN happen in handguns.....if the wrong powder is used. The answer is simply (as suggested by others already) to use a FAST enough powder....or a powder with enough volume to substantially FILL the case....or a hot enough load (enough powder) ....to prevent the problem from appearing.

So, for 357 magnum cases, using light loads (38 Special or 38 Special +P)....use a fast powder such as Bullseye, Red Dot, Titewad, Clays, etc.etc. etc. Or, use a high-volume powder such as Trail Boss. Or, load up a bit into +P territory, with powders such as Unique, HP38, W231, etc., etc., etc. DO NOT do light loads with such powders as 2400, Blue Dot, H110, SR4759, etc. etc.

Simple rule. If you follow this concept, you'll likely never have a problem. Plus, you'll get better results anyway.