powder for 357

I am trying to work up a load for a buddy of mine. He found some off the shelf ammo that runs a 158gr JHP right at 1140fps in a 5" revolver, and I am going to try and duplicate that load for him. I have 300MP and Unique that I use most of the time for my loads. 300MP does not like to be downloaded, so it is out. Unique looks like I might be able to get there, and that is where I am going to start. But Unique tends to be a bit dirty in my experience. I also have some W231 and blue dot. 231 is dirty, and I am not sure I can get that velocity, and I am leery of blue dot as I have had previous pressure spikes that I do not like. From my research, 2400 looks like it can be loaded up or down and still perform well...I just have to find it. Anybody have any other suggestions? or a little 2400 they'd be willing to trade?

I think all your presumptions are correct. It's the loading down part that is the biggest problem with the "ideal" powder. IME I would first consider 4227 and a magnum primer (actually a magnum primer is a good idea for all these suggestions). It is slower than 300MP or H-110 but tolerates being loaded down and loves being packed tight in a case. Being so slow it tends to shoot a bit softer, fills the case and is not temp sensitive. AA9 is considered a ball powder version of 2400 in burn rate. It is certainly clean burning. 2400 should be an ideal powder. My only real concern about Blue Dot (a great powder) is it seems sensitive in handguns. I load it in my guns but would prefer a more mistake proof powder when loading for others. I agree that Unique may be too fast for a jacketed bullet of this weight. It is worth a try though. There are plenty of other powders to consider but this covers all the burn rates.

So all things considered I would try 4227 first and AA9 second.

I run Blue Dot in my dad's 357 Mag ammo as a slightly reduced load. We wanted a 357 Mag round, but not a fire breathing dragon load. I've used H110 with good results as a max load. I run somewhere around 9 or 10 grains of Blue Dot with a 158 grain HP and it works well out of the revolver and his lever gun. It's a good medium to mild load of 357 Mag. We've shot it out to 100 yards on steel and it performs great.

I do need to add that I have thousands of small pistol primers and zero small pistol mag primers. Alliant suggests non magnum for their 300mp, and it has worked great for me. Unique doesn't need mag primers either, and those are the two powders that I usually use. I believe that H110 both needs a mag primer and does not like to be loaded down. If I can't find 2400, maybe I'll give blue dot another try. Does blue dot need a mag primer? edit: I looked on Alliant's website. Blue Dot does not need a mag primer. Maybe that's why I had issues with it in the past. I used to always use mag primers for 357.

I use standard small pistol primers. I have used the magnum nickel primers, but my Taurus revolver doesn't hit it hard enough for 100% ignition. So I run a brass cup standard primer in our 357 Mag ammo, and it works great. I would certainly run a magnum primer for H100 or 300 MP.

You would run a Magnum primer for 300mp? Alliant specifically states to use standard primer for 300MP. I have used standard primers with very good results with 300MP. I seem to remember reading somewhere that part of the selling point of the 300mp powder is that it did not need mag primers.

I would, yes. It's a slower burning pistol powder, like H110. I have not read or seen where they specifically state this. I'd love to know, though. Their online data shows a Fed 100, which is a standard primer. It certainly can't hurt to run a magnum with the high charge loads they use.

It has been pretty well known over the decades that a standard or a magnum primer is pretty much what the manufacturer says it is. WW primers have always been hotter than some other brands. Some WW primers say on the box "for standard or magnum uses". I suggest some research on the primers you have.

2400 I think is the powder for you.

I know you’ve already stated that H110 isn’t right for what you want but I want to reiterate it. Don’t download H110.

I just emailed them. We'll see what their response is.

Yes, I already have 300MP which likes to be loaded near max. Just like H110...although it may be safer to download it. Don't know as I've never tried. I do really like the 300MP, but I also want a midrange load which can't be achieved with 300MP.

Accurate No 5 or HS-6 will both do exactly what you want. I load both for mild 357 loads.

The hotter you load Unique the cleaner it burns. If you have Unique try that. But that's the fastest burning power I would try to duplicate that load with.

I have burned many pounds of unique in a 357 mag and its great especially at max data not as dirty as one thinks under the top of the charts data. 2400 is good for speed but produces a big flash and I have seen better accuracy from unique in a hand cannon. H110 shoots very accurate in a 158 or 180 gr bullet at max data.

Lots of good powder for a 357 mag available in many different places

I am no fan of Unique but it's much cleaner when it's loaded up. You'd have to experiment to find the velocity you want.

In my experience and the experience of many others, 99% of loads out there are not affected to a noticeable level between the use of magnum and standard primers.

I would try Power Pistol or HS-6. I might have a sealed container of one of those.

2400 produced by far the most accurate load I have ever made in .357 but it's hard to find in the last five years compared to others. It is likely a little hotter than you desire but not a real pounder.

I have a pound of Power Pistol I got from somebody on the forum a year or two ago. I use Unique, Universal, and 231 for my 357, and likely won’t use the Power Pistol. So if unclebubba needs it, I’ll sell or swap it. What I need is H4831 sc or R17.

I bought Unique and have used it specifically for 180 and 200 grain subsonic. Although a bit dirty, it has served me well for that purpose. I have never tried to load it up near max because it was so dirty. Maybe I'll give it a try and see if it works. I've got plenty of it.
According to Alliant, Power pistol only gives 1078 fps at max load. Maybe I should start using that for my subsonics. LOL.

Well, it seems that Alliant's position is that you are supposed to stick with book loads and not deviate or experiment at all. Even with different bullets. Thier response wasn't helpful in the least.

"Michael,

You need to look to your recipe. If the recipe calls for a standard primer, you need to use the standard primer. The same is true if tested with a magnum primer.

Load data is based around pressures. Using the incorrect primer can lead to unsatisfactory loads due to pressures and even catastrophic results.

Alliant does not have the data for the Hornady bullet. When I look to the Hornady #11 Reloading Handbook, they tested their loads with Winchester Small Pistol Magnum (WSPM) primers.

Unfortunately, this data is copyrighted and you will either need to contact Hornady or purchase the handbook.

Thanks,

Duane V. /Technical Service Representative

2299 Snake River Ave.

Lewiston, ID 83501

Alliant/Blazer/CCI/Speer"

Regarding Blue Dot, look at the warning on Alliant's website regarding Blue Dot in .357 with light ( 125 gr ) bullets. I realize you are talking about 158 grain but that was enough to make me walk away from using it in .357 at all. It works great in 10MM but I am using a 180 gr bullet there. I switched to Accurate #7 several years ago and have not looked back.

For .357 "moderate" loads I have tried several powders but my go to is Accurate #7. I was using Win296 for full power loads and tried some less potent loads using Accurate #9. After I moved to accurate #7 I was really pleased with the results. I even use it in .44 mag with 185 gr JHP now.

Regarding Unique, I tried that many moons ago and was not impressed. I have a can of the "new" Unique but AA #7 works so well I will probably only use it for .38 special.

I prefer Unique, and I really don't find it any more dirty than most other handgun powders. I don't leave my firearms dirty, so it doesn't matter to me. What does matter, is an 8# jug of unique lasts forever and works in most mf my handguns, including 357. Give it a try and see for yourself. YMMV.

I only use 2 powders for handgun caliber rounds
Unique and 2400
Standard primers

"dirty " burning and "unburned powder " doesn't figure into
any of my loading or shooting at all. I have many cleaning
patches and cleaning rods.
Hitting where I'm aiming is what I strive for

Good Luck

Agreed. Unique does a little of everything but nothing well. As far as dirty goes...I clean my stuff more than most people but when my hands are greasy after handling the cylinder of a single action, it's dirty powder. Yes, it cleans up some with more pressure.

The only reason I keep some is it's okay with cast bullets in .30 cal rifles at low velocity...something it was not made for.

So this will blow your mind. For the 357 Magnum, Nosler lists a max charge of Blue Dot with a 158 grain JHP as 10.4 grains with a magnum primer, while Alliant lists their max data with a 158 grain JHP at 10.2 grains, and a standard primer. Higher powder charge and magnum primer. Yes, a different bullet, but it won't vary that much.


https://www.nosler.com/357-magnum

https://www.alliantpowder.com/reloaders/powderlist.aspx?type=1&powderid=10&cartridge=28


Speer load data interchanges between CCI 500 and 550 (standard and magnum), mainly magnum on the slow burning magnum handgun powders.

https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/357_Magnum_135_GHDP.pdf


Yes, you need to apply the right primer to your cartridge, powder and bullet application. Saying you can't deviate from the factory load data at all is Alliant playing it safe, very safe. Most of my ammo I load for reduced recoil and subsonics comes from applying the right powders with the right powder with the cartridge and bullet application. You think there's any load data for my 223/5.56, 112 grain AR-15 cycling subsonic ammo? No way. It is created from my experience with powders and primers and applying it to the specific task. You can easily apply back off you load data a few tenths when using a magnum primer. And vice versa. But there are some powders I just won't use a standard primer on, like H110 and 300 MP in the 357 Mag.

And there's the reason why all the internet whiners regarding no deviation from "the book" are full of it.

Books don't even agree.

Use your head and everything will be okay.