Why don't we see magnesium guns?

[KarateHottie93]

Mag Tactical lowers are prone to to breaking due to the magnesium alloy and aren't very popular for that simple reason. They are prone to breaking at the buffer tube just like polymer lowers. Mag Tac.had to to also add material around the pin holes to keep the lowers from breaking.

Yes I do have one Mag Tactical lower but I would never ever buy another one. I also have one New Frontier Armory polymer lower, again I will never buy another.

Yes magnesium and polymer lowers are definitely lighter than aluminum. But being lighter definitely comes at a cost to durability and strength.

I don't know about older attempts at polymer lowers but I've been shooting this polymer lower ATI Omni for 11 years now and it's been ultra reliable. I've put countless rounds through it and have undoubtedly mistreated it at times. It's held up perfect though. Not sure how their current ones that also have a polymer upper are but this old metal upper one is great. Like it's good enough that I put a (fairly expensive for it's day) MWI rail on it.

Also added in some other random polymer guns to the picture, and then a scandium gun cause why not? Then I added in my current Skilsaw cause it's the only piece of magnesium I own to my knowledge lol. Well then again I drive a 2016 Jetta so I guess that has some too, based off previous comments?

My point to this...well not with this exact saw cause it's new and hasn't been used yet, but these things get knocked around, dropped, beat up, and left out in the elements all the time. Plus they're constantly getting scratched and scuffed just due to the nature of their purpose. Circular saws have a really hard life. The Skilsaw Mag 77 came out I think in the 70's and is undoubtedly the single most used circular saw still today. You never really hear stories of them breaking or degrading. I mean obviously there are always gonna be some examples out there but for the most part, they're known as pretty durable. I just have a hard time understanding how these things can be so amazing if magnesium is so bad.

 

[crestoncowboy]

Magnesium has been used in cars and saws forever. GM and Ford have billions invested in magnesium now. Most, if not all, pro chain saws have a two piece crankcase made of magnesium. Some have magnesium pistons. And yes ive seen plenty crack. As far as fire....magnesium has been used off and on for pistons from the 20s on. Even in F1.

Id guess its too brittle for much gun use. Its also more costly to make than aluminum while being only slightly lighter.

 

[12Bravo20]

I don't know about older attempts at polymer lowers but I've been shooting this polymer lower ATI Omni for 11 years now and it's been ultra reliable. I've put countless rounds through it and have undoubtedly mistreated it at times. It's held up perfect though. Not sure how their current ones that also have a polymer upper are but this old metal upper one is great. Like it's good enough that I put a (fairly expensive for it's day) MWI rail on it.

Also added in some other random polymer guns to the picture, and then a scandium gun cause why not? Then I added in my current Skilsaw cause it's the only piece of magnesium I own to my knowledge lol. Well then again I drive a 2016 Jetta so I guess that has some too, based off previous comments?

My point to this...well not with this exact saw cause it's new and hasn't been used yet, but these things get knocked around, dropped, beat up, and left out in the elements all the time. Plus they're constantly getting scratched and scuffed just due to the nature of their purpose. Circular saws have a really hard life. The Skilsaw Mag 77 came out I think in the 70's and is undoubtedly the single most used circular saw still today. You never really hear stories of them breaking or degrading. I mean obviously there are always gonna be some examples out there but for the most part, they're known as pretty durable. I just have a hard time understanding how these things can be so amazing if magnesium is so bad.

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ATI and a few others that make polymer lowers insert some type of metal reenforcement into the lower at the buffer tube. With the ATI, the buffer tube actually thread directly into the metal insert. And this is why some are not as prone to breaking at that location. All it takes is a simple online search to see plenty of examples of unreinforced polymer lowers breaking at the buffer tube. This is a very common issue with polymer lowers, especially if a carbine stock is used.

Everyone needs to remember that most things made from magnesium are some type of alloy. And it will depend on what other types of metals the magnesium is mixed with on how strong items are.

As far as I can remember MAG Tactical is the only company that madden AR lower from a magnesium alloy. They had to ads extra material around all pin holes to keep the lower from breaking. And those lowers were prone to breaking right at the buffer tube just like a lot of polymer lowers can. Plus the alloy they used did not hold up well and was susceptible to cracking.

Here is a google search showing problems with the MAG Tactical lowers. https://www.google.com/search?client=safari&rls=en&q=mag+tactical+lower+problems&ie=UTF-8&oe=UTF-8

As far as revolvers or other types of firearms made from magnesium alloys, again it depends on the exact make up of the alloy on if they hold up over time or not.

Magnesium is a good metal when properly alloyed for some things, but firearms is not one of them.

 

[CapnMac]

Magnesium is also used in

Tracer compounds . . .

 

[CapnMac]

One of the issues for forging is the size of the presses wanted.

The Germans in WWII built some gigantic presses, which astounded Allied observers when discovered. As in 500 ton presses. And the Soviets promptly hauled away every one they could grab. So, the USAF started up an emergency capability contract to build both 100 and 500 ton presses to make aerospace parts. These are not small machines, five stories tall in some cases.

Like as not, the biggest hurdle for magnesium as firearm metallurgy is in getting a finish to adhere to it. It's probably not going to accept chrome or nitride treatments, and, naturally, it will not rust blue. So, if you are left with cerrocoating or the like, there are less-expensive metals to use as a base.

 

[12Bravo20]

One of the issues for forging is the size of the presses wanted.

The Germans in WWII built some gigantic presses, which astounded Allied observers when discovered. As in 500 ton presses. And the Soviets promptly hauled away every one they could grab. So, the USAF started up an emergency capability contract to build both 100 and 500 ton presses to make aerospace parts. These are not small machines, five stories tall in some cases.

Like as not, the biggest hurdle for magnesium as firearm metallurgy is in getting a finish to adhere to it. It's probably not going to accept chrome or nitride treatments, and, naturally, it will not rust blue. So, if you are left with cerrocoating or the like, there are less-expensive metals to use as a base.

And the average punch press used to make most everyday parts with stamping dies is normally between 65 tons and 100 tons with a few up to 150 tons. Now this is for smaller parts. Something like the old automotive body parts from the 30's to 50's would definitely take a bigger press.

One of the places I worked as a tool and die maker made semi trailer parts and most of the punch press and press brakes were between 65 and 100 tons each. We made all the parts for trailer sliding axles and also the bogies that held the tires.

 

[CapnMac]

would definitely take a bigger press.

Found this image:

Check out the caption (emphasis added)

The first, made by Mesta Machinery, weighs 8000 tonnes and is 27 metres high. Its table measures 7900*3700 mm and has a stroke of 1800 mm. Aluminium giant Alcoa, which has operated the machine since 1955, bought it from the US government in 1982. In 2009, the press had to stop for repairs due to cracks in the basement. The retrofit cost about $100 million and will guarantee at least another 50 years of operation.

8 x 4 m table (±26' x 12') is a significant dimension.

Lockheed Skunk Works actually contracted a press maker to build the custom presses needed to make titanium parts for the SR-71/YA-12 program. Allegedly there was a separate security clearance to enter the titanium machining area.

Industrial stuff will boggle the mind until you get some experience being around it (or running same).

 

[entropy]

It might even work on AK trunnions......

 

[gunmechanic]

I have welded it before but that is the extent of my dealing with magnesium.Welded motorcycle cases that were made out of it. It tig welded easily ,like welding aluminum .

 

[lysanderxiii]

Like as not, the biggest hurdle for magnesium as firearm metallurgy is in getting a finish to adhere to it. It's probably not going to accept chrome or nitride treatments, and, naturally, it will not rust blue. So, if you are left with cerrocoating or the like, there are less-expensive metals to use as a base.

Magnesium is anodized just like aluminum.

 

[Kingcreek]

Years ago, a couple of us were shooting at a private “dump” on a family farm. I learned that fired tracers can start a mag wheel on fire and that once ignited it is damn near impossible to extinguish.

 

[12Bravo20]

Magnesium is like white phosphorus when it comes to putting a fire out. You have to smother it and the best way is to bury it with dirt. You do not want to use water to put out a fire with either material.

A solid chunk of magnesium is harder to light compared to magnesium dust and small shavings.

Magnesium alloys are not as strong as 7075 T6 aluminum. Plus the magnesium alloys are more prone to stress fractures/cracks. This along with the extra cost is why one doesn't see magnesium alloys being used very often for firearm frames and receivers.

 

[Howland937]

I don't have much experience with magnesium, except to say that years ago I had a handful of Shimano Chronarch MG reels I used frequently.
Lightest, smoothest reels I'd ever used. Every one had a warning label on or in the box (paraphrasing)
"Do not use this reel in brackish or salt water environments as damage from corrosion will occur".