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Discussion Starter #1
I heard that the LF195 has a shelf life? Something to do with the primers.

True or not?

I want to start stock piling some 5.7x28 ammo for long term storage, I've got 30 year old .223/.308/8mm/7.62x30/30-06 ammo already, and they all go pop every time.

I'd like some decent 5.7x28 ammo so my son can be shooting in 20-30 years when he's older.
 

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I have seen a lot of talk on other forums that because of the 195 lead free primers, the rounds may only have a shelf life of 10 years or so. I don't know if anyone can answer this question 100% for sure - but reloaders familiar with reloading technology claim this to be the case.

The 197 is not lead free, however. So, long term storage should probably be of the 197 round.
 

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I have to call bull **** on this whole deal 10 years is just not long ..... seal it in ammo cans with siclia and it should out last you......
 

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No, supposedly it is the primer that degrades w/o lead - once again, I am not a reloader. But, I have seen many people who CLAIM to know about it confirm this. Who knows.
 

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I have heard the same thing but we will not know for 10 + years if that is the case.......
 

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No mystery or BS just basic science.
Removing the lead and replacing it with an aluminum compound is the reason for this. The aluminum compound oxidizes over time. You can increase the amount of time it takes to break down the primer compound by removing all oxygen from the container. sealing the can keeps out miosture but you must remove the O2. There is a procedure fro flushing out the O2 with an inert gas outlined elswhere
 

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close the problem is outside pressure will get in sooner or later. You need to purge the container of O2 and fill it with an inert noble gas (argon) at an equalized pressure.
 

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Discussion Starter #9
I get the "wine enthusiast" magazine... they offer Nitrogen in a can, its got a small plastic spray tube like WD-40.... you're supposed to spray the gas into the half empty bottle to displace the O2 so the wine doesnt turn to vinegar.

That'd probably work by spraying into an ammo can?
 

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The problem with that would be the nitrogen gas. It's not a noble gas (inert) and would react with the primers. Plus it's a large can to flush. I have seen pic were someone has put a metal shrader valve into the ammo can side, evacueted the air and then let the Argon flow in until it hit an equal pressure with the atmosphere
 

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If the rounds are not lacquered to be air tight (primers, bullets) and you evacuate the air from a sealed container, wouldn't you also be evacuating the air from the rounds themselves? And if this is the case, when you place an inert gas into the sealed ammo box wouldn't some of the inert gas also enter into the rounds?

If this happens, then would this not affect the performance of the powder as it is later ignited?

I guess that a way around this would be to evacuate the ammo can, replace the vacume with inert gas, then before use, evacuate the inert gas, then replace the vacume with regular air.

Seems to me that it would be better just to evacuate the air from the ammo can and leave it evacuated. Then maybe about two or three days before you open the ammo can, replace the air and allow time for air equalization within the round.

I am no way even slightly knowledgeable about this but being a recent graduate from engineering school, it stand to reason that if the rounds are not completly sealed then whateve is evacuated and replaced, will be replaced within the round itself. And if ideed you use an inert gas, I am pretty sure that it will affect the performance of the ignited powder later on.
 

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To HKSD9

The short answer is that the propellants contain their own oxidizers and are not dependant on outside air.

This is how rockets and explosives are used in the vacuum of outer space.
 

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OK, I am a civil guy not a chemical guy. But I think that I still need a little more convincing. Is there a place/site that you can refer me to so that I can read up on this?

Thanks
 

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the problem with just evacuting the can is the outside pressure trying to force it's way in and it will sooner or later. The cans weren't designed to hold a vacuum.

As to were to read up, I would start with college intro to chemistery book
 

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commander zippy said:
No mystery or BS just basic science.
Removing the lead and replacing it with an aluminum compound is the reason for this. The aluminum compound oxidizes over time.
Sorry to burst your bubble but lead also oxidizes, although at a slower rate. I have unfired lead .38 Spl rounds from the 1930s that are pure white on the bullet from oxidation. However this is from improper storage for the last 70+ years. Keep your ammo dry and at a reasonable temp away from humidity and i would be willing to bet that LF ammo will last a LONG LONG time.
 

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OK, after reviewing my college chemistry book on oxidation and using the following equation

KO,NO5+ 2S+4C = 2CO2 + N + KS2

it is evident to see that any gas (air or whatever) or lack of gas will not affect the performance of the projectile except that there will be only a miniscule reduction in the amount of gas pressure generated by the oxidation of the chemicals, if not within a vacume. In a 1500:1 ratio, the amount of gas or lack of gas in the cartridge is praticaly non-existant within the pressure gradient.

The 2CO2 + N producing the pressure while the KS2 (potasium sulfide) produces the smoke and the peculiar smell of the burnt gunpowder.

So by using additional chemicals to reduce the amount of potasium sulfide, it would result in a cleaner burning powder with less residue (less smoke) and if properly balanced, could even increase the effectiveness and pressure gradient of the burn.

So to make another assumption, the remenants of the unburned powder is due to the less than 100% combustion of the powder which could be caused by a whole other set of factors, including but not limited to, burn rate, pressure gradient, ect...

Been a long time since I took chemistry. :oops:
 

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Burst all you want its a fact that new primers are more prone to storage issues and faster break down then older primer compounds. The removing of oxygen extends the storage life of the newer compound primers.

I never stated that the lead didnot oxidize.

so go burst your own bubble
 

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commander zippy said:
No mystery or BS just basic science.
Removing the lead and replacing it with an aluminum compound is the reason for this. The aluminum compound oxidizes over time.
hmmm you state that removing the lead and replacing it with aluminum is why the LF primers won't last. Reason ? Aluminum oxidizes. You make no reference to the fact that lead also oxidizes, as do most metals. This statment would lead most people to the assumption that lead does not oxidize and would be spreading, although not intentionally, misinformation.
 

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I'm just a dumbold welder, but aluminum ixidized nearly imediately when touching air this is why we use an inert shielding gas when TIG welding aluminum. It also keeps out harmful hydrogen that embrittles metal and welds. Lead does oxidize but at an extremely slow rate. I'm not an engimeneer or anything like that just a dumbold welder, but I do know that all metals oxidize but lead and gold are the slowest. even stainless rusts (oxidizes) just slower than most metals. add any type of acid to it and it does it faster. even lemon and lime juice will cause stainless to rust. The pipes I weld on everyday are stainless and they are completely oxidized through from the waste products of pork processing.

We also prevent the pork from oxidizing by flooding blast chillers with nitrogen gas and the railcars that ship it. Even when frozen things will oxidize so we keep the oxygen away from it.

I had some bad remington primers last month in their lead-free range ammo. almost 1 out of 7 wouldn't fire (9mm) and remington said it was because of their lead-free primer. I think I like lead primers.
 
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