shelf life of Unique powder

I just bought two pounds of Hercules Unique that my gun dealer forgot he had in the back. I'm not worried about it at all.
 
I think I remember this being Hercules powder you have, if so, here's Hercules data from 4/1985.

abk.jpg


Loading data should come close to the manufacture date, which means old powder needs old data, not new data.

Oh well, I looked back again and it's only 5 years old, so use Alliant data.
 
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Well I finally got the reloader all "dusted off", and up and running. My powder seemed to smell fine, not much of an odor really.

I got a box of 158gn LSWC with 8gn of Unique loaded. Hopefully I will be able to head to the range on Tuesday evening after the holiday to test them out.
 
If powder is stored in glass IN THE DARK it is probably ok. If stored where light hits it, maybe not. Glass is NOT a good idea in general. Drop it and BINGO, there it is, all over the place. Powder is light sensitive - UV can seriously degrade it.

FWIW
Dale53
 
Well I finally got the reloader all "dusted off", and up and running. My powder seemed to smell fine, not much of an odor really.

I got a box of 158gn LSWC with 8gn of Unique loaded. Hopefully I will be able to head to the range on Tuesday evening after the holiday to test them out.

Adagna, I'm guessing based upon bullet description that these are .357magnum loads...... There are sources that show 8 grains of Unique under 158 LSWC........usually as max. There are many reputable sources that stop at 7.5 grains. I have pressure reports of28kCUP with 7.5 and 40k+ with 8-8.2. Unique is a fine propellent and extremely versatile but pressures tend to climb rapidly once you exceed its optimum pressure range. If these are .357 mag loads you intend to test you are starting TOO HIGH. Please be safe.
 
I have some cans of powder that are at least twenty years old, and they are fine. They look good, smell good and still go bang.

I just fired about twenty five rounds of .38 Spl I loaded with 148 grain wadcutters and and WW231. The box was dated 1989. Worked great.

I've also fired commercially loaded military ammo as old as 1938 and it was fine.

I regularly shoot surplus ammo that is forty to fifty years old and have never had a problem.
 
Adagna, I'm guessing based upon bullet description that these are .357magnum loads...... There are sources that show 8 grains of Unique under 158 LSWC........usually as max. There are many reputable sources that stop at 7.5 grains. I have pressure reports of28kCUP with 7.5 and 40k+ with 8-8.2. Unique is a fine propellent and extremely versatile but pressures tend to climb rapidly once you exceed its optimum pressure range. If these are .357 mag loads you intend to test you are starting TOO HIGH. Please be safe.

These are 357 mags. I actually only had time to load about a dozen rounds this morning. So I guess its good that I didn't get too invested in that load if its not correct.

Several sources I found said 8, and I was previously loading 7.5. Should I back it down to 7.5 again or go lower then that?

I just did a little checking and Alliant shows a recommended 6gn of unique for a 158gn LSWC, but doesn't say whether this is a starting or max load.
 
I am using a can of Blue Dot I recently purchased from my friendly neighborhood gun junky Dan. The top was dusty and slightly corroded so he gave it to me for $5.00. It was unopened from the factory. I loaded some 10mm and it seemed to be fine. The original price tag was very cheap, so I know it's pretty old. The powder was dry, smelled good, and the little blue dots were still blue.
 
Adagna, Your 8 grain load is probably safe.....but it at or above max in enough sources that I would want to work up to it. If you previously used 7.5 and it worked well then 7.5 should be fine. Many many sources list that loading as safe. Personally I have used Unique only for middle loads- preferring slower burnrate powders for top .357 loads. I've shot many .357s loaded with 6.3gr of Unique and 158 grain SWCs-that is equivalent to a .38 Special +P plus a smidgeon (1000-1100 fps from a 4 inch barrell)
 
The SAAMI pressure specs for .357 Mag are still 35,000 psi or 45,000 cup. I have seen the cup pressure spec listed at 46,000 cup IIRC in Speer #10.

The Hercules data I posted on page #3 doesn't show any pressures over 40,000 cup, including 8.5 gr with a 158 gr LRN.
 
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I think I will go ahead and back it down a little, no sense in over doing it. I will try loading a batch of 6, 6.5, and 7 since I already know what 7.5 feels like, and already have a few at 8. I'm sure Alliant knows their powder best and they are saying 6.
 
I think that would be prudent. As for Aliant data.....it is has been about as useless as a congressman. Now that Alliant owns Speer, their website data has been upgraded a little but due to past experience with disengenuous Alliant data I always check real data sources.
 
I am still shooting Unique and Bullseye from 1964. Both have been stored indoors , climate controlled. After 45 years, both still shoot and chronograph as if they were just bought new yesterday.
 
I recently used the last of a can of Unique I bought back in the 60's. I did not notice any difference in its response after 40 years of storage. I used it off and on over the years.
 
There is an argument that 2400 has changed formulations, based mostly on some of the old Keith loads which are now considered too hot.
My old can of Unique is dated 1965 on the bottom, I bought it in Rockford, IL the guy time/stamped everything.
I don’t use it much, it will probably see me out.
 
Just fired off my first batch of reloads from my Unique and they went off without a hitch. I definitely liked the 6 grain loads over the 7-8 grain loads. Although accuracy was fairly similar between the loads at my measly 10 yards, which is more or less what I would expect.
 
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