shelf life ??

[JEBar]

what have you found the shelf life (for lack of a better term) of factory loaded ammo .. .. how about hand loads .. .. decades ago I purchased some WWII military surplus 30-06 ammo .... the casings have tarnished with time but they still go boom .... after a bit of looking I just retrieved 12 30-30 bullets from the vault that I loaded on 8-9-94 .... my hope is to run them through a chrony within the next few days and I'm looking forward to the results

[CT_Shooter]

... after a bit of looking I just retrieved 12 30-30 bullets from the vault that I loaded on 8-9-94 .... my hope is to run them through a chrony within the next few days and I'm looking forward to the results

I am, too, JEBar. I've read that an opened canister of smokeless powder will get more potent, grain for grain, as it ages; but if it's in a handloaded cartridge, it retains its original potency and so does factory ammo.

…Once a container has been opened, (and even slightly before it's opened), the chemicals used for 'drying' the powder "off-gas". That doesn't, to my knowledge, change the burn characteristics of the powder, but it does change its "bulk density". You may recall that this came home to me 'in spades' a few years back when I took the .338 MAI to Colorado for the first time. The charges of BL-C(2) were not even 'warm' let alone hot, but I was blowing primers - REALLY blowing primers when I got down there. Turns out, the powder I used for loading THOSE cartridges up was the last of a cannister of BL-C(2) that I had had for almost 30 years, and that I used almost the last of loading those cartridges.

A 50-grain charge of "new" powder will contain less energy than a 50-grain charge of "old" powder because the "old" powder will have a higher bulk density than a "new" cannister of powder does. So...

My suggestion is that you work up on the TRULY 'low' side of "book" charges to start with 'til you get to 'know' that cannister of powder. AND, when you get a new cannister, don't expect it to produce the same MVs or pressures that a really old cannister did.

This isn't an issue once a cartridge is loaded because the chemical energy is fixed forever - the amount of powder doesn't change, only it's weight. That's why milsurp ammo from the late '30s (and especially the nazi 8x56R stuff), is still good to this day.

[JEBar]

very interesting .... I've never heard that theory expressed

[RanchRoper]

I watched a video not too long ago where a guy was shooting 1960 vintage factory ammo; there was no difference he said from current ammo. No misfires, etc. The deal breaker is how it is stored apparently. Must be kept cool and dry.

[snell]

I still have some 270 ammo I loaded in the 90s and when I take it out to plink it is right on call with freshly loaded ammo. Storage conditions has a lot to do with it. Wild swings in temp or humidity are supposed to be bad for ammo.

[tx gunrunner]

I have 10,000 rd of 45 ACP I loaded in 1980 for my Mac 10 and 1911 . Once a year I test all my combat guns and use this ammo and it has never missed a heart beat box . I store ALL ammo in a steel box in cool room .

[Squatch]

I think sealed ammo and modern powders are very stable. Opened powders are subject to many things like, were they left open for a while? Humid conditions? I've read some stories about old powder being hotter but some say it's just compaction of the powder over time.

Also some have attributed it to changes in the formula. This after a post about loading some rounds with a very old keg and then some more with newer. The specified powder HAD gone through a manufacturing change in recent years.

[JEBar]

after a bit of looking I just retrieved 12 30-30 bullets from the vault that I loaded on 8-9-94 .... my hope is to run them through a chrony within the next few days and I'm looking forward to the results

well, they all went boom .... they averaged 2160 fps at 10' from the muzzle .... very respectable speed for 30-30 ammo

[RanchRoper]

I sure hope it has a long shelf life....I'm stockpiling factory ammo. About 3500 rounds of 45 Colt stashed away now....

[Henry88]

Since this is in the Reloading section I won't mention the wax on .22s can dry and some of the old military stuff used corrosive primers, but since this is the Reloading forum I won't mention it..............