Powder for .357 Magnum?

We used a lot of Blue Dot in 357's in the past, but do remember the warnings coming out about it and have restricted it to 10mm only now. Perhaps when they started checking pressures with strain gauges vs copper crusher they were seeing transient spikes above what the CUP were showing? Never heard the whole story of what and why...but it's probably a good idea to follow the cautions. Especially since there is 2400 which works most excellently in 357's we don't miss the Blue Dot at all.

ColtPythonElite said:

And that doesn't make a bit of sense when they have data for 110 and 140 loads.

Before that warning, I loaded thousands of Blue Dot 125 JHPs. I was using the starting load from my Speer manual. They sure had a big boom and lots fire.

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This is nothing new. The warning has been there for at least 3 years. From what I understand they have done more complex pressure testing than was possible in the past and discovered potentially dangerous pressure spikes in certain cases. Lymans 49th which first came out in 2008 and was last printed in 2013 includes data for a 125gr jacketed bullet. I am guessing this problem was discovered between 2013 and 2015

That warning has been out for close to 10 years.

If I were a beginner, I would look at Unique, followed by BE-86, and then Power Pistol for .357.

There is hardly anything you can't load with Unique.

I really like BE86 for stout plinking loads in 357mag. About 100-150fps less than full magnum velocity, but still a good stout load, and not case position sensitive like so many other powders.

For full magnum velocity, I like 2400 and N-110 in revolver loads, and 300-MP in rifles.

Blue Dot is a great powder for .357, jus't don't used compressed loads, it can cause damage crane stretching on Pythons.

I like 2400 for magnum loads, Unique for middle range, and Trail Boss for light loads, all with 158 grain SWCs. I use the same powders in .44 magnum as well.

Lot's of good powders out there...currently using AA#5 under a 158gr SJSHP.

I'll just say......2400 powder and the 357 Magnum have been a perfect match since the 1930's.

If the OP's just getting back into the game and wants to feel comfortable, grab some UNIQUE.
It's been around for well over 100 years ... for good reason.

I have tried Blue Dot in .357 mag. pistol my best results were with 158-180 gr jacketed bullets.
I have better results with Accurate #7 and #9, and 2400 for 2.75" and 4" barreled 357 mag .revolvers.

Chopperbobby said:

Thank you all who offered help with this.
It seems to me that there is some doubt about using this particular powder, and some of you like it.
My problem is that I have been away so long that I am just like a beginner.
I am concerned about using my BLUE DOT powder. It is also used in shotgun ammo, and I think I would like something more specific to the .357. If I remember correctly I used Hogden powder before, but I don't know which kind.
Any ideas about this?
Bob

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Alliant 2400 has been THE .357 Magnum powder for decades. It's a good choice. If you like the flash and boom look to Hodgdon H110/ Winchester W296. If you don't want either look at the list I posted in Post #20.

I have been spoiled with 2400 in 357. I have went full strength and 20% down-loaded loads. I feel it has a larger window in charges. The H110/W296 has me leary from the 3% rule. So I have never tried it.
Tried the 300MP out. That is pretty stout magnum powder. More than I really wanted.
Tested some Blue Dot, but not enough to feel I have a say so.

Just got the 2018 Hodgdon Reloading Manual (magazine format). FIVE new handgun powders. Really interested in whether IMR Blue will be much better than Alliant Blue Dot. Also real interested in CFE Pistol for 9mm and .40, but it might make an excellent medium powder for .357 mag.

Hodgdon's H110 works great for me.

~15.5 gr. with a 158 gr. bullet will get you a real stiff load.

jski said:

Hodgdon's H110 works great for me.

~15.5 gr. with a 158 gr. bullet will get you a real stiff load.

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I guess charging 16.8gr would be out of the question then.

I am using BE-86 with great success, here are a couple of loads tried.

Bullet/Powder/Load/OAL/No. rounds and FPS/SD/ES/firearm
158gn Hornady XTP JHP BE-86 7.5 1.58 10/1165 18 59 colt python
158gn Xtr FP BE-86 7.1 1.58 1 0/1092 14 49 colt python
158gn Xtr FP BE-86 7.1 1.58 3/1080 5 10 colt python

LeftyTSGC

ArchAngelCD said:

I guess charging 16.8gr would be out of the question then.

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To be clear, the current Hodgdon .357 magnum load data for H110/W296 with a jacketed 158 grain bullet (the Hornady 158XTP HP) is a starting load of 15.0 and a max of 16.7 grains at an OAL of 1.580". The .357 magnum loads for this powder were for years given as "DNR" - do not reduce. In recent years they have gone to publishing a start-max charge weight range for them.

Anecdotally, as you increase charge weight towards the maximum the standard deviation and spread of the load decreases significantly, and the combustion becomes visibly more complete. Accuracy will nearly always be best at max as well. It's safe to load lighter-than-max charges with H110/W296, but it was never intended to be run there. 2400 is more flexible in this regard. It is slightly faster burning, limiting velocity potential to roughly 90 percent of H110/W296 at typical revolver barrel lengths, but has a more typical performance at less than maximum charge weights. H110/W296 pulls further ahead as barrel length increases.

LeftyTSGC said:

I am using BE-86 with great success...

Bullet/Powder/Load/OAL/No. rounds and FPS/SD/ES/firearm
158gn Hornady XTP JHP BE-86 7.5 1.58 10/1165 18 59 colt python

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Interesting, I tried BE86 in 357 magnum with a 125gr. bullet a few days ago. At 9.0 grains (9.1 is listed as max by Alliant) it made on average.. 1202.5fps.. heh. Less than 40fps more than your 158 grain load, which is 0.2gr. further away from the Alliant max. Looks like you really need to use slower powders with 125 grain bullets.

ray15 said:

It's safe to load lighter-than-max charges with H110/W296, but it was never intended to be run there.

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That powder in the form if H110 was specifically designed to load the 30 Carbine for military ammo. They were not looking to reduce loads. It had to shoot every time and push the bullet to terminal velocities. (Whether or not it succeeded is questionable)

My three powders for the 357 have been AA#9, 2400, and H110. All have worked very well. I don't load light loads in that caliber. If I want light loads I shoot 38 spl loads. My go to deer load is a 180 XTP over a stiff load of H110 and a CCI mag primer, but this is out of a Ruger GP 100. This load has taken at least a half dozen whitetails out to 50 yards.

When I push to max loads (for my .357) it quickly becomes uncomfortable to shoot. And when I go to the range I'm looking to have a good time.

That's one of the reasons I love my .30 Carbine Blackhawk. Even with max loads (15.5 gr of H110 + 115 gr GC, Linotype bullets) the weight of the Blackhawk tames the beast. And it's just plain fun to shoot.