I cleaned out and re-arranged my ammo locker yesterday and found some .357 Mag ammo that I loaded a few years ago that I haven't fired since I first loaded it. I'm concerned about whether or not it can be fired safely.

First off, when I loaded this ammo several years ago, I was using it in a Colt Python 4". I don't have that gun anymore, and the .357 Magnum that I currently have is a S&W 686+ 7-shot L-frame with a 2-1/2" barrel.

I loaded the ammo using brand-new primed R-P nickel-plated brass and Sierra 125 gr. JHP bullets. Here's the issue: I used 14.6 gr. of Blue Dot powder.

I don't actually remember shooting this load, but my range notes indicate that it was a stout load, but there was no primer cratering when I shot it in the Python.

I just looked in my four reloading manuals. Three of them do not list Blue Dot powder. The one manual that does list it indicates that 12.0 gr. is a maximum load! I don't intend to reload more of it -- I just hate to dissassemble the 60 rounds I have, and I would rather fire it if it's safe.

Does anyone here have any more info on the use of Blue Dot powder with a 125 gr jacketed bullet in the .357 Mag? What's your opinion on the safety of this load?

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NRA, IACP, INEOA, MCRGO

I tried Blue Dot years ago in the .357 and gave up on it. The big problem with Blue Dot is that you get to a point where small increases in powder charges cause significant increases in pressure - not a good characteristic. It didn't offer any advantages over other powders, and I stopped loading it. I would be hesitant to use those reloads in another revolver since they may be very near or even over maximum. It is always better to start low and work up loads carefully for each gun.

Since it's an overcharge in the manual that has Blue Dot listed I would not fire those bullets in my gun. Pull them if you need the components.

I checked all my manuals. Speer says 13.0, Lyman says 13.3, and Alliant (the manufacturer of Blue Dot) says 14.5. But Alliant's data is for a 125g JSP, not a JHP. I sometimes exceed what the powder manufacturer says, but only if I have a another reputed source (manual from a bullet manufacturer, for example) that has tested and approved what I am proposing to load. Your load exceeds the limits of all the sources I have, but only by 0.1g. I don't think I'd fire them in the Smith. But I would not be concerned about firing them off in the much heavier built Ruger GP100.
Assuming that you don't have a GP100, try pulling one bullet so see how difficult it will be. If it comes out without difficulty, I'd disassemble all of them and recover the components.
I actually like Blue Dot for the 357 magnum. I use 11.0g of it with 158g jacketed bullets.

Thanks for all the answers, guys.

I think that I'll let discretion be the bettor part of valor here and disassemble the ammo. I have a collet-type bullet puller that works very well in my RCBS press, so it shouldn't take long to pull them. I'll discard the powder. I can remove the decapping pin from my Dillon 550 press and resize & bell the cases without disturbing the primers.

Thanks again for your prompt replies.

__________________
NRA, IACP, INEOA, MCRGO