Shelf life of CMP mil-surp ammo

[Quoheleth]

I'm thinking about picking up a couple spam cans of the CMP ammo for my Garand while it's still "reasonable". I know it's decades old as it is - what do you think a reasonable life expectancy of this stuff is?

Is it better left sealed in its cans or to break it open, check for bad apples, and then repackage it in something like the flip-top steel ammo cans?

Q

 

[jcwit]

You probably won't live long enough to see it go bad. I've been shooting some ammo from WW2 with Nazi Swatakas on it.

 

[Zanad]

Is it better left sealed in its cans or to break it open, check for bad apples, and then repackage it in something like the flip-top steel ammo cans?

do this and you'll be good.

 

[Tinpig]

I've shot many spam cans of CMP HXP .30-06, all from the late '60s early '70s in clips and bandoliers and in 20 rd. cardboard boxes. Not saying it's not possible, but not a single round was defective, corroded, or badly tarnished.
Unless there's obvious damage to the hermetically sealed spam can I'd leave it alone until you want to shoot it.

Tinpig

 

[Smokey Joe]

OOOh! Collectible!!

J C Witt--You said

I've been shooting some ammo from WW2 with Nazi Swatakas on it.

I think you could get enough $$ for that from cartridge collectors, or collectors of Nazi stuff, to more than pay for an equivalent amount of brand new 8mm ammo! Especially if (ugh!) the packaging is also in XLNT condition! (Collectors seem to prize packaging even more than the stuff within it--dumb IMNSHO, but there you are.) Anyhow, were I you, I'd check into selling that Nazi ammo before shooting up any more of it.

 

[Tim the student]

If the exterior of the can looks fine (no major corrosion, punctures etc) I'd definitely leave it as is. If it looks bad, I may open it, check it, and store it in an airtight can with some desiccant. Then again, I may not.

I'd bet that ammo (properly stored) will be good for at least another 40 years.

 

[essayons21]

I've shot 1000 rounds of (non-CMP) 1975 Korean M2 Ball with only 1 hangfire.

Gone through about the same amount of Pyrkal (HXP) 1971 CMP ball with no problems.

I would be curious to find the actual shelf life of WWII-era ammunition, but I doubt I will live long enough to find out.

 

[ABTOMAT]

Anyone know how the old US surplus lasts? I have about 35 pounds of '50s Twin Cities M2 on its way.

 

[Ian Sean]

I have about 100 or so rounds left of 1920's .30-06 Match ammo.

Went through 5 rounds of it last year for the heck of it, still accurate (out of my 03a3) think I will save the rest until it hits 100.

I still have several hundred 1930's 8mm on hand.

Stored properly, cool, dry, low humidity, ammo should last indefinately, your lifetime at least.

 

[VT Deer Hunter]

7.62x54r ammo from the 1800s when they first made it still works i'm sure.

 

[ball3006]

It is probably 50 years old already so it shoud be good for awhile. I have never had a round fail to go bang. I reload so it should be good for another 50 or so years....chris3

 

[Firehand]

If properly stored, the stuff lasts for decades. Sometimes a bunch of them.

Few years back I opened a can of .303 I'd had sitting for years and found that the ammo is British made in 1943. I've fired one box of it, and it all still fired perfectly with good accuracy.

 

[Tom609]

Your grandkids will probably be asking the same question. If the can looks good, I too would leave it alone.

 

[Larry E]

A friend gave me some Canadian military 9x19 ammo loaded in 1943 that had been stored loose in a cloth bag in a hunting guide's cabin in BC for who knows how long. I fired it from the HIgh Power I had at the time, and chronographed it. It all went bang and averaged right around 1275 fps too, so the stories about WW II Canadian military 9 mm ammo being loaded hot for submachine guns may be true.

 

[General Geoff]

Centerfire ammo, when stored properly, has yet to reach its lifespan. My guess is that it will last at least two hundred years, possibly more, in a low humidity environment, especially brass cased, jacketed ammo (which is what most surplus is). Steel cased ammo might not last quite as long due to corrosion.

 

[BruceB]

Milsurp can be highly-variable.

For example, Portuguese ammo has a good reputation for quality. In the early '90s, I bought 2000 rounds of '84-dated Portuguese 7.92x57 for use in my MG42. The stuff looked like new, but on arrival it was giving about 1%-2% misfires in the machinegun.I finally used the last of it in 1997, and by then the misfires were running about 30%-40%! Talk about frustrating....

This lot of ammo really went downhill very quickly, and I don't know why.

I strongly recommend firing a judicious-sized sample of any newly-acquired ammo before depending on it, and also firing a reasonable-sized test lot every year or so. If it's becoming unreliable, it would be MUCH better to find out before you really need it.

 

[Dr.Rob]

I had some steel cased Korean war vintage 45 ACP that I fired off without a hitch. Seemed that ammo was loaded pretty hot--no failures to fire. It wasn't stored in a sealed spam can, just a cardboard box that had been in a sock drawer for 35+ years.

If the tin/spam can is sealed, leave it be.

 

[MarcoPolo]

My job in the Air Force is to take care of munitions. On a regular basis we issue ammo that was made during WWII and it works fine. When we inspect munitions sealed in the Spam style can we do not open it unless we see damage to the can. The cans are designed to provide the maximum protection to the enclosed munitions and are packed in low humidity environments to avoid moisture. Your ammo will be fine for many years to come. If something doesn’t work properly it’s not because it wasn’t packed proper, it’s more likely there was an issue during manufacturing.

 

[Remander]

I have some old 30.06 cmp ammo in a wood crate and cans inside. Sits in my garage. Works when I bring some out to shoot. Seems pretty durable.

 

[RockyMtnTactical]

Indefinite, as long as it is stored well.