Aluminum framed guns for very long term storage.

[1990SHADOWBOATS]

I have done some research on steel, aluminum and polymer framed guns for very long term storage.
As far as I can tell steel will be the best. “There are some 200 year old guns still in working order”
But I can’t find anything on aluminum framed guns. I know it can become brittle due to heat but how about age? Does anyone here have any information on this? I have some doubts of the polymer framed guns due to degassing but will include some for “just in case I am wrong”
Of course this all depends on me doing my part for correct storage along with the ammo and manuals and repair parts and springs.
This is NOT a flame war on what’s best I am just trying to find out some information.

 

[gbw]

“There are some 200 year old guns still in working order”
But I can’t find anything on aluminum framed guns.

And you likely won't, IIRC aluminum has not existed as a usable metal for 200 years yet, let alone been used to manufacture a gun that old.

Many things are made from aluminum or an alloy that are intended to last indefinitely, so I wouldn't worry about it too much.

But I am curious: Why do you want to store a gun for more than 200 years and how would you do it?

 

[rcmodel]

There are still aluminum airplanes flying that were built prior to and during WWII.
That was nearly 75 years ago.

I'd say any high-quality aluminum frame gun in storage should last way longer then that.

And that will be longer then you will last anyway.

rc

 

[gbw]

Sorry for double post!

 

[1990SHADOWBOATS]

I should have said 200 year old all steel guns.

The reason, insurance for the future.

 

[firesky101]

I do not see a whole lot of 200yr old steel w/o rust, but I do see lots of 50+yr old aluminum w/o rust and the same with 20+yr old polymer.

 

[The Lone Haranguer]

The same measures you take to protect all steel guns should work for aluminum-framed ones as well.

 

[x_wrench]

i really think the storage conditions will have the most effect on whatever you store. if you couldgive them a generous coating of rust preventative, and vacuum seal them. then get them into a good ammo can with a good seal, and store them in a cool dry place, they should last longer than all of the relatives that you have alive at the time of your death. hopefully, you will live a long time, and have great grandchildren to leave them to.

 

[RaceM]

The main thing with aluminum is to make sure it's clean. Salt residue from sweat or atmosphere will combine with moisture and start to corrode it. Clean well, maybe even to detail stripping, oil/coat in preservative, then vacuum seal.

 

[dogrunner]

200 years? How long you gonna live!

 

[Ranger30-06]

From my experiences at work, aluminum has only one feature going for it: its light. While steel will rust, aluminum corrodes and is also MUCH harder to treat than steel. Just look at cast aluminum vs cast iron engines; the aluminum ones burn out a heck lot faster than the cast iron ones...

I say this because there is almost no chance I would count on an aluminum frame gun to be even in a dozen pieces after 100, much less 200, years.

 

[56hawk]

Well, I have aluminum framed guns that are over 60 years old, and polymer framed guns that are over forty years old. None of them show any signs of degrading. Wouldn't worry about it too much.

 

[dogrunner]

I wouldn't worry at all. I remember a lightweight framed Colt Cobra that was retrieved from a salt water estuary long ago. Only the frame, cylinder and bbl were remotely salvageable. That aluminum frame was so corroded that it looked as tho termites had their way with it. A fellow I worked with cleaned the frame, spray painted it black, replaced the internals and shot the heck out of it. Franky I was surprised it held......that thing was an utter wreck, little discernable rifling left and the cylinder had to be honed internally to get it to permit ejecting ctg's. I truly don't think that a steel framed piece would have fared any better. Anyway, it worked and it impressed me with the relative durability (and strength) of aluminum.........and remember, the event I reference was nearly fifty years ago.......metallurgy has vastly improved since as have finishes.

 

[Elkins45]

The very tip top of the Washington Monument is an aluminum pyramid about the size of your fist. At the time (mid to late 1800's) that quantity of metallic aluminum was a rare and unusual object indeed. It was chosen to cap such an auspicious monument because the designers knew it would maintain its integrity when exposed to the elements for nearly forever.

 

[rodregier]

Keep in mind that in the mid to late 1800's metallic aluminum was a scarce precious metal with unit pricing higher than gold at the time. Royalty also had aluminium flatware as prestige items in the same era. A new refining process for aluminum in the late 1880's dramatically changed the unit cost equation for aluminum

http://en.wikipedia.org/wiki/Aluminum#History

With modest effort to protect it, aluminum will easily last 200 years in fabricated items. Lot of industry experience with old aluminum airframes. Primary limit on airframe life is stress and vibration, not age alone.

 

[1911Jeeper]

Alloys in the 6000 and 7000 series groups contain silicon and magnesium in approximate proportions to form magnesium silicide, thus making them heat-treatable. Major alloy in this series is 6061, one of the most versatile of the heat-treatable alloys. Though less strong than most of the 2000 or 7000 alloys, the magnesium-silicon (or magnesium-silicide) alloys posses good formability and corrosion resistance, with medium strength. 7075 exhibits similar properties. AR-15's are often made from 6061 or 7075.

Raw Aluminum is remarkable for its ability to resist corrosion due to the phenomenon of passivation. Aluminum alloy surfaces will keep their apparent shine in a dry environment due to the natural formation of a clear, protective layer of aluminum oxide. Aluminum oxide is responsible for the resistance of metallic aluminum to weathering. Metallic aluminum is very reactive with atmospheric oxygen, and a thin passivation layer of alumina (4 nm thickness) forms in about 100 picoseconds on any exposed aluminum surface. This layer protects the metal from further oxidation. The thickness and properties of this oxide layer can be enhanced using a process called anodizing.

Aluminum firearms are usually hard-coat anodized. Anodizing creates a harder surface more resistant to wear and to corrosion.

Anodizing is an electrolytic passivation process used to increase the thickness of the natural corrosion resistant oxide layer on the surface of metal parts.

Clean, oil and store your aluminum firearms just like any other firearms. Under normal storage conditions, age has no effect on aluminum.





.

 

[barnbwt]

200 years? How long you gonna live!

"I plan to live forever, of course, but barring that, I'd settle for a couple thousand years. Heck, even 500 would be pretty nice..."

Nah, seriously, the only real issue to worry about with aluminum is dissimilar metal corrosion. When aluminum butts against steel (or some other metals) corrosive forces are greatly enhanced. Keeping the gun dry/oiled at the interface prevents this, but it's an issue nonetheless. Aluminum will definitely corrode on its own, and suprisingly fast in certain alloys/applications like the aircraft industry(I've seen machined parts with damage inches deep), but only when it is consistently wet or exposed to salt.

TCB

 

[Weevil]

As long as you're not gonna store it in a bucket of bleach or saltwater I wouldn't expect any problems. If it's from a quality maker I'm sure they've taken corrosion resistance into account when designing and choosing materials.

Like any long term storage use some grease or cosmoline that won't evaporate or run off like oil, keep it in as non-corrosive or non-reactive container as possible and use a desiccant, and then store it in a cool dry area of your home.


Just don't stick in a leather holster in a cardboard shoebox in the laundry room closet and wonder why it rotted away.

 

[YankeeFlyr]

Like he said...

I'm with 1911Jeeper; Al alloys will self-anodize to a very hard protective surface oxide. Unless continually disturbed it will stop further corrosion in a normal atmosphere.

Furthermore, while fatigue limits are well known for iron alloys (steel), aluminum cycle numbers are rather...indefinite...for some alloys (like 2024 for aircraft).

(A few years back, and maybe still there was a small fleet of DC-3s operating in Florida with over 100,000 hours on the airframes. Back in the 1930s they didn't have the structural optimization software they do now, so they overbuilt them all.)

 

[Certaindeaf]

Death ray guns will be made of osmium, crystal and trinimagich and laugh at your popgun.

 

[4thPointOfContact]

The very tip top of the Washington Monument is an aluminum pyramid about the size of your fist. At the time (mid to late 1800's) that quantity of metallic aluminum was a rare and unusual object indeed. It was chosen to cap such an auspicious monument because the designers knew it would maintain its integrity when exposed to the elements for nearly forever.

A substance more precious than gold.

 

[fletcher]

I agree with what is noted above about keeping the aluminum clean and dry for long term storage. Chlorides in salts will attack the passive layer which will cause pitting, and electrolytes hanging around in any areas where aluminum is touching steel can result in galvanic corrosion. For a properly heat treated aluminum alloy, age will have no measurable effect on the mechanical properties.

With a little bit of care prior to storage, it should last forever.

In reference to an above post - for 7000 series alloys, silicon plays little role in overall strengthening. 7000 series alloys are an Al-Cu-Mg-Zn system, with those four elements contributing to strengthening through formation of various intermetallics. Si is important to 6000 series alloys, which are an Al-Mg-Si system.