Old IMR Powder - Range Report

[mic2377]

Hi All,

I wanted to post some first-hand experience I had with a stash of old IMR powder I was given. It was from an old hunter who did low volume 308 reloading, and he had some old stocks of IMR 4064, 4350, and 3031. When I say old, I mean that it came in a 1 lb steel cans, so it must be at least 25-30 years old. I was going to toss it all and fertilize the lawn, but I instead got curious and decided to load up some 223 with some of the 3031.

My observations - cans were unrusted, and were sealed tight when I got them. When I opened them up and looked at the powder, it looked the dark grey that new IMR powder is. I have a poor sense of smell, so I can't comment whether it had an acidic smell or not.

When I started loading, I noticed it gave off a little bit of rusty brown dust. Other than that, no difficulties.

Now to range time - loads were 23.5 and 24.0 gr of 3031, 40 gr v-max, CCI-450 primer, and COAL of 2.23. 23.5 gr cycled fine in my 18" 3-gun rifle, but did not lock back on last round. 24.0 cycled fine too, locked back, and to my suprise turned out a 0.8 MOA group. Since these rounds were intended as no more than plinking ammo, I didn't bother to bring a chrono, but they are probably on the weak side. Either way, no guns were hurt in this experience.

I will say though that I had a less than positive experience shooting some old 45 colt ammo that someone gave me. After 2/10 did not fire, I promptly junked the rest. My guess is that primers tend to go bad sooner than powder does.

I probably got lucky not blowing something up, but I read somewhere that as powder ages it tends to get weaker, so hence the necessity for a higher than minimum load to get the rifle to cycle. No matter what I am going to use up the rest of the 3031 at least.

[anachronism]

I have IMR powders, and they're no where near 20 years old. One of the cans even says "Dupont". I just checked them, all smell and look normal.

[warpspeed]

I got an old can from my dad of DuPont IMR 4895. Its says "24.95" on it in pen. I plan on loading some one of these days to see. It came with old LR primers too.

The shotgun primers he had all have gone bang so I suspect the LR will too.

[Guy Neill]

The res dust is a sign of deterioration.

Guy

[Intel6]

Of course Guy already caught it but a red dust coming off the powder when you agitate it is a specific sign that the chemical compunds of the powder are breaking down. Normal powder does give off a dust but that is typically the graphite coating they put on the powder and when you look carefully at the dust it is black/grey.

Neal in AZ

Edited February 11, 2013 by Intel6

[lynn jones]

the imr 4064 doesn't meter well.

[fltbed]

Of course Guy already caught it but a red dust coming off the powder when you agitate it is a specific sign that the chemical compunds of the powder are breaking down. Normal powder does give off a dust but that is typically the graphite coating they put on the powder and when you look carefully at the dust it is black/grey.

Neal in AZ

DOH!

I’ve already loaded (and shot) two 20+ year old open cans of IMR 4320 that had the red dust thing going on.

223 for my AR.

55 gr. Hornady Z-max

25.6 gr. IMR 4320

CCI #400 SR primer

3020 f.p.s. out of my 18” with low ES and SD’s in the low teens.

.75 MOA out of my rifle.

I guess I got lucky but I won’t be doing that again!

Thanks for the info!

Jeff

[mic2377]

Truthfully, I did a little research and knew that red dust is indeed a sign of powder breakdown. There was not much of it though and I figured that the worst thing that would happen would be a dud or a hangfire.I was so curious that I could not resist loading up a couple rounds before heading to the range. Alas, fate was on my side.

Standard disclaimer - do not let this be advice to use questionable components. Just sharing my experience, and YMMV.

[Shadowrider]

Stored properly powder and primers will last over 100 years. High temps as in over 100 degrees is what gets them along with wide swings in temp.