Interesting experience with 2400 today...

by Brian A, Thursday, October 22, 2015, 13:20 (3324 days ago)

I loaded up a few 357 magnum cases with 158 gr cast SWC bullets over 14 gr of 2400 from an old square one pound can I have been using for years, set off by Rem 2 1/2 standard small pistol primers in Winchester brass. Loaded six into the chambers of a S&W Mod. 27 and it sounded like a rifle going off when firing the first three. Decided to check the brass before continuing to shoot and saw the primers were all flat, then found out all three cases were sticky and took a good whack to extract them.

I next tried one in a 357 magnum Contender and the primer was flat and case sticky again. I have loaded a couple hundred 20 gr loads with this powder in 44 magnums under cast and jacketed bullets with no signs of high pressures at all, so doubt it is the powder. My manuals list max charges with 2400 for the 357 and 158 gr cast bullets with these primers as 15 to 15.5 gr, so had thought this would be a safe place to start and had hoped this would be good for use in K-frame Smiths.

Anyone have an idea what may be going on? This can is down to just a tiny bit of powder left and next is a newer container of 2400 that is still sealed and only about six or seven years old, that I know has been stored in a cool, dry place since new.