38 Special +P loads

[44Caliber]

I wish to load Winchester 231 powder with a 125 gr JSP using a 357 magnum S&W 6 inch revolver. Hodgdon technical support recommends Winchester 231powder.... 5.3 grains. Does anybody have any experience with a more powerful load using Winchester 231 powder???

Winchester 231 is identical to Hodgdon HP-38 powder.

[Shadow9mm]

According to my hornady manual 5.4g is the max standard load, and 5.7g is the max +p load.

My sierra manual shows a max 6.3g for standard and 6.8g for +p

Why not get some 357 brass and make light 357s, instead of hot 38s? Same dies.

[44Caliber]

Thanks for the info and suggestions.I am really surprised at the wide range between 5.7 gr to 6.8 gr for the +P load

[Shadow9mm]

Sierra loads tend to be on the hot or full power side imho.

For reference, from the sierra manual for 357 mag, it shows a start of 8.1g with 9.1g of 231 as the max load. Just to show the difference.

I have heard of people putting 357 mag loads in 38spl cases. Especially if you have actually 38spl guns i would not do it in case of a mix up. To me it seems unwise in general.

[BrBa]

W231 is a great all around powder for standard pressure loads in multiple cartridges, but it has a fast burn rate which doesn't make it a great choice for .357 mag. I would look for something with a slower burn rate, especially since you have that 6" barrel. You'll get more velocity and likely less recoil with a slower powder compared with W231.

[Unclenick]

Do not put 357 Mag loads in 38 Special cases unless you seat the bullet out to 357 Magnum COL. Otherwise, you will be increasing pressure by lighting the powder up in a tighter space under the bullet.

Regarding the variation in published data, notice what the test gun was. Hodgdon is reporting a load fired in the SAAMI 7.710" Velocity and Pressure (V&P) test barrel, which is a closed-throat barrel used to mimic a single-shot handgun. Sierra is using the SAAMI 5.631" V&P barrel, which has a 0.008" vent at 1.623 inches from the breech to mimic a revolver barrel/cylinder gap, which does drop some pressure. Additionally, the Sierra bullet is a little shorter than the Hornady XTP, which also lowers pressure where the COL and all else are the same.

So, there are variables here. None will take you over 357 Magnum pressures, though. I think my approach would be to start with Hodgdon's load and look at velocity and see if it is satisfactory. If so, just stop there. Your 6-inch 357 Mag revolver barrel, if all its other dimensions and your chamber dimensions matched the vented SAAMI V&P barrel, it would be expected to take a cartridge that produces 940 fps in that V&P barrel up to 1010 fps. That would be so if you had 38 Special chambers. Yours are longer and will drop pressure more, so you are going to need more powder to get there than a 38 Special revolver of otherwise-matching dimensions would. BTW, that number is an average of ten shots measured with an optical chronograph whose midpoint between screens is 15 feet from the muzzle. See what the 5.3-grain load does over a chronograph with that spacing from your gun. If your fastest chamber still has it under 1010 fps, you can creep it up toward the heavier published loads. I just wouldn’t go over 1010 fps (average twelve shots since you have a six-gun) if you want to be at +P pressures.

[Nick_C_S]

You mention a Smith 357 6" revolver. Specifically, what model is it?

I load a lot of 38+P 125 HP's with W231/HP38 - have for decades.

Just so I'm clear: I'm using a 38 Special case.

The charge weight I use is 5.6 grains. Yields 978 f/s through a Smith Model 67 (a +P rated 38 Special gun), 4" bbl. It's a nice, snappy round. Sierra's max in my book's edition is 5.8 grains. I suppose one could increase the charge weights if being shot in a 357 gun, but I'd discourage it. At that point, I'd move to a 357 case, and use the appropriate load data for 357 Mag.

I'm curious what is your load purpose? Why increase the charge?

[44 AMP]

Do not put 357 Mag loads in 38 Special cases unless you seat the bullet out to 357 Magnum COL.

Pardon me for being a jerk, but I don't see how a difference of 0.04" can matter all that much.

[Unclenick]

I was generalizing, but it actually depends on the bullet and powder. With a short bullet, the pressure increase is only a few percent, like about 6% for a 125-grain bullet, so it wouldn't matter there, as that lies within normal shot-to-shot pressure variation. But at the other extreme, by the time you put a long, heavy cast bullet in, like the RCBS 240 gr FP GC design, the 0.04 is changing the powder space under the bullet by a bigger percentage, and I can get pressure to increase in the software by 37% doing that, not to mention the shorter load being more highly compressed than the programs suggest you can get into a case without distorting the brass, which is another issue with some 357 loads in the smaller case.

[Paul B.]

From the Winchester loading manual #15: W231, 125 gr. JHP .38 Spl. brass.

Start: 4.8 gr./ 840 FPS/ 14,100 PSI
Max: 5.3 gr./ 935 FPS/ 17,200 PSI

Using .357 Magnum brass, W231, 125 gr JHP:8.1 gr./1460 FPS/42,500 C.U.P.
Paul B.

[BrBa]

I load a lot of 38+P 125 HP's with W231/HP38 - have for decades.

Nick,

I'm curious about your accuracy results with W231 +p loads and 125 gr bullets. I generally stick to 158 gr both fmj and coated lead, and honestly haven't had any luck with accuracy at higher pressures. 4.0 grains with 158 gr coated and 4.2 gr with 158 fmj both have excellent accuracy in all my revolvers. If I go much beyond that the groups really start to open up.

Thanks!

[44Caliber]

Thanks to all of you who replied. We have a great Steel Pin range at our club and I am trying to establish a load sufficient to knock the plates over. I had been using W-231 powder 5.4 gr in 38 +P cases, 125 gr copper plated Rainier bullet in my S&W 357 magnum Model 686 6 inch barrel. I have a lot of 126 gr bullets on hand. I am going to switch to a heavier 158 gr bullet and see those results.

[44 AMP]

Knocking over plates is a matter of momentum. Lighter bullets have less than heavier bullets.

A fast light bullet "slaps" the plate. A slower heavier one "pushes" the plate. Mass, inertia, and momentum are involved. Generally speaking you need to slap the plate hard in order to get to move the way it does when "pushed".

Fast powders generally reach cartridge max pressure yielding a lower velocity than slower powders.

There's no free lunch...sorry

[Shadow9mm]

I agree that more bullet weight is needed to nock over pins. Light fast bullets do poorly for that.

Looking at my hornady manual w231 is a decent performer with 158s compared to other powders.

[Nick_C_S]

Nick, I'm curious about your accuracy results with W231 +p loads and 125 gr bullets.

I may not be the best person to ask as I don't do a lot of distance shooting with that ammo. I will say that it has been my experience that the bullet itself seems to be the primary factor in short-range handgun accuracy.

I use an Everglade's 125gn HP for most of my 125+P ammo. They seem to go pretty straight; but if I was interested distance, I'd likely move to a Hornady XTP; and probably a FP. I know XTP's go pretty straight with 240's in 44 Mag - where I do do some distance shooting (50 yds occasionally - 100 when I was younger).

In 38 Special over the years, I've found that 125's tend to worm around a little more than 158's. And 158 Lead SWC's seem to be the straightest. I never did much experimenting with accuracy going up the charge weight ladder. 4.0grains of W231 under 158's tend to be my go-to charge weight for target ammo and never thought much about increasing.