/k/ - Weapons

They can't be reloaded and they have issues with expansion that brass solves.

Low quality ammo tends to be aluminum.

>>533591

>They can't be reloaded

I can see this as a problem for the consumer market, but not military.

>Expansion

I thought aluminium was soft and malleable?

>>533607

>literally just 'no u'

Top wew.

>>533581

This thread might of interest mate:

http://forums.delphiforums.com/autogun/messages/7121/1

>>533597

http://www.thefirearmblog.com/blog/2017/11/28/lsat-cased-telescoped-ammunition-problem-cookoff-brief-thougts-002-follow/

>The notion that heat gets “evacuated” with the brass case is overstated, because what happens with a polymer case is while the heat of combustion is the same, it is actually trapped in the case because the case acts as an insulator.

I know better than to trust what a woman says on a technical subject but why wouldn't the same apply for an Al case?

>>533592

Too soft. Instead of stretching (Like brass) it'll crack and tear.

>>533597

And this. Brass, like lead might be seriously old tech, but they work flipping amazingly for all that.

>>533668

Oh. I don't care about that.

Most my ammo ends up being steel cased anyway.

>>533607

>>533615

>>533616

>>533643

>>533654

>>533659

>>533668

This kike shit needs to be ban on sight. Reported. Kill yourself.

>>533668

>says the noguns to the hasguns

>>533691

>he has no guns

>>533696

He is right though, you're acting like triggered bitch over a pointless discussion. Everyone knows Argentina is the whitest anyway

>this thread

cuck/int/ was a mistake

>>533653

Flechettes are more useful for pistols than for rifles.

1. Flechette doesn't have to travel far, only 50m. Wind, leaves and other things affecting the low-grain projectiles dont matter.

2. In body, flechettes turn sideways and tear more tissue, increasing chance that they'll hit a blood vessel.

3. Recoil is negligible, which is a huge component of handgun accuracy. With burst option can have groupings of three to five flechettes at 50 yards, which is sure to hit a blood vessel.

4. The size of the flechette is tiny, so its possible to stack 50-100 of them in a handgun.

5. It doesn't have to go as far, so the powder load can be reduced. It doesn't have to hit as hard, so powder load is reduced again. It doesn't have to travel fast, it just needs to be supersonic for 50m so the fin-stabilization will work. All this results in a far smaller casing. In fact nail gun shells can launch a 14 grain flechette at 850m/s (345J). That's slightly weaker than 9mm (450J) but you can fire them in bursts of three to raise total energy, they penetrate armor better than 9mm, and they disintegrate completely in target which reduces any chance they'll over penetrate.

Just popping in to remind you guys filter by flag would be a great feature see you later have fun with the d&c

>>533718

I'm not even Brittish.

>>533717

>We know you are a proxyfag, you mutt.

nope. britfag just had his posting history erased. the vols are sympathetic to the cuckchan spam.

>>533634

>>533708

I was a fucking idiot to even reply seriously in this thread at all.

Everyone in this thread is subhuman. I hope you all get breast cancer you humongous faggots.

>>533769

If it makes you feel any better, I appreciated your contribution to thread despite the faggotry on display.

>>533772

I never said anything about you being white or not.

>implying country with no guns contributes anything

>>533776

The only instance of "achmed" I've referenced was in regards to a migrant attempting to rape your wife.

The question mark flag contributed far more than you did.

>>533771

Thanks, you're a peach. That does make me feel better.

No homo.

>>533797

You post like a nigger

>>533779

The UK does have quite a few migrants, yes.

Pretty sure the natives are still white, though.

>>533797

>balkanize meme

go back to cuckchan. only there does this stupid meme have some oxygen to thrive.

>>533816

That's actually pretty hilarious, I wouldn't have thought that it could get quite hot enough.

Do you recall where this was mentioned, I can't find a reference.

>>533867

It's to find a new /k/, anon.

>>533581

>>533776

Stop pretending to be a victim. Vols can see your post history across multiple threads and all you've done the last few days is post >muh huwite memeshit if you're the same britbong from the other threads. It's pretty much shitposting at this point.

Anyone can make a good point and be right, but still be a massive fucking faggot for the other 90% of their post. Your posts were deleted so I can't really confirm or not even if /k/ vols are fags irl, but even faggots can do the right thing when it comes to bans.

>>533816

I assumed it was something along these lines. In electrical wiring the aerospace and manufacturing industries tried using aluminum wiring instead of copper at one point too save a buck and the results were disastrous. You'd think they'd figure it out and question if higher heat output is really a good idea.

Why don't we just use cobalt for casings though given the abundance of it from zinc mining and relative uselessness of it due to toxicity?

>>533770

Contrary to what your media would have you believe, not all content is supposed to be comical in nature

>>533708

Well, that wasn't exactly the main topic of my post, but indeed, flechettes seem to be a best. I guess you could design a simple blowback pistol for this new ammo, reducing the costs even more. Thin of a Stechkin with enough magazine capacity to be actually useful.

>>533581

Brass expands to seal the entire chamber. Part of why steel cases are so dirty is because they don't expand like brass, so they allow gun powder residue to get into the chamber around the casing; if you shoot brass after shooting a bunch of steel ammo, you can start getting jams because the brass is expanding and sticking to the dirt in the chamber. Aluminum is soft like brass, but it's also brittle and will crack or split rather than form a seal with the chamber.

Brass also has a higher specific heat density and absorbs more heat; when spent brass gets ejected, it takes more waste heat with it than steel or aluminum does, which is why all other things being equal, shooting brass-cased ammo will take longer to overheat the gun than shooting aluminum or steel-cased ammo.

>>533609

No, because you're looking at the wrong problem. Metals conduct heat, plastic does not. The plastic case acts as an insulator and reduces heat in the chamber by preventing any from being transferred to it. Metal cases ABSORB more heat from the chamber and take it with them. Brass will absorb more heat and remove it from the gun than aluminum will. Shoot some brass and aluminum ammo, then grab a spent case immediately after it comes out of the gun; notice how the aluminum case feels cooler to the touch? It didn't absorb as much heat.

The plastic prevents heat conduction; metal conducts heat no matter what, but the different types of metal RETAIN different levels of heat and take it with them when ejected.

Think of it like this: You can keep the inside of a pan dry by placing a glass of water inside it; the glass holds all the water and none of it gets into the pan. That's polymer-cased ammo. Now pour the water into the pan and compare how much gets removed when you insert a rag (aluminum) and a sponge (brass); which one absorbed more water and removed it from the pan?

>>533624

Yup. Lead is used because it has the perfect properties of malleability, density, melting temperature, etc. Other elements are rarer (and thus more expensive), or harder to process because they have to be machined (tungsten), or aren't dense enough, or are too hard and just poke a hole instead of expanding, etc.

About the only material found to be better than lead is an alloy of osmium and iridium; they're the two densest metals, and when alloyed they make the perfect bullet material that is even harder than tungsten (making an excellent AP round) but also brittle so that they fragment after penetration, even in soft tissue (making them far more lethal than current AP rounds). The reason nobody makes bullets with an osmium-iridium core is because nobody wants ammo that costs $5,000 a shot. The only way for either metal to become common enough that we could use it for bullets is if we started mining asteroids on a massive scale.

>>533871

>cobalt is useless due to toxicity

>let's put it in a high temperature, high friction environment with miniature explosions right next to someone's face and hope microscopic cobalt dust doesn't become a health issue that gets someone sued decades later when it's found that shooting cobalt-cased ammo is almost as bad as asbestos

>>534356

Brilliant post. Your pan analogy shows excellent abstract thinking.

>>534358

It's not that bad unless you're inhaling cobalt dust for breakfast. No worse than the other shit already in ammunition.

It's like how depleted uranium hard drives are radioactive, but sticking thin sheet metal over it is typically enough to prevent any lingering alpha particles from doing shit. Can't be any worse than the uranium used in artillery/tank ammunition and armor I figure.

>>534395

would be enough*

Uranium hard drives don't exist yet.

>>534356

> alloy of osmium and iridium

Ah. Someone was listening to m sperging about osmiridium. I know osmium by itself has a mohs hardness of 7 and is a little brittle. I know osmiridum is harder, but I don't know about it being brittle.

So seeing as the actual reason why aluminum isn't a typically used case I've came to 2 ideas

Wouldn't a open bolt solve the problem of heating?

Would folding the metal in a specific pattern help reduce any important tearing/cracks in the explosion?

>>534520

>Wouldn't a open bolt solve the problem of heating?

Open bolt mostly helps the problem of cookoffs because it doesn't keep the ammo in the already hot chamber. Today it's only used in GPMGs where volume of fire is more important that accuracy. Even SMGs are closed bolt today. So even if simply using an open bolt weapon was an option, you'd be forced to use it only for machine guns.

>>534395

1) Brass, steel, and aluminum cases all produce metallic dust due to friction, heat, etc. Copper and lead fouling in the barrel isn't the only issue you deal with.

2) Several European countries experimenting with lead-free ammunition had soldiers get sick and suffer respiratory problems because the 'environmentally friendly' ammo was producing dust particles that got inhaled every time a soldier fired his weapon. It's an issue.

3) If you're coating cobalt in another metal to avoid soldiers inhaling tiny, toxic cobalt particles, why not just make the casing out of that metal instead of cobalt?

4) Is cobalt even a good candidate for ammo casings? In terms of heat capacity, brittleness, softness, expansion, durability, etc. would it even work in the first place?

>>534405

I didn't read most of the thread, just responded to OP. Osmium-iridium bullets have been a scifi wetdream for years.

>>534520

Open-bolt guns are only used on machine guns that prioritize volume of fire over precision. They avoid cook-offs by not storing a live round in a hot chamber, they're not actually any cooler. In fact, there's a reason they change barrels every 200 rounds or so.

Federal law also bans any semi-auto firearm from having an open bolt, as it would be readily converted to full-auto.

The LSAT gun has a rotating chamber that isn't physically a part of the barrel; between the plastic casing acting as an insulator and no heat conduction from the barrel, the chamber remains fairly cool. I'm wondering: revolver cannons used on aircraft can be gas-operated, and use 3 or more chambers to keep up a high rate of fire, and only the barrel overheats, not the chambers, so there's no risk of a cookoff even with a rate of fire of 2,000+ RPM. Would it be possible to scale that down into a GPMG or HMG, with a revolving chamber, quick-change barrel, and insanely high rate of fire? Think of an MG3 that doesn't overheat, or a mini gun that's actually man-portable. That would be insane.

>folding metal in a specific pattern

No. You're talking about a sheet of metal as thin as your fingernail, or thinner. You're not getting multiple layers, at least not of any useful thickness. You should also research how ammunition cases are made; they're drawn, not hammered and forged. It's cool to study, and you'll immediately see why folding metal wouldn't work.

Another issue is that gun barrels with folded layers of metal blow up. Damascus-barrel shotguns are made in the same manner as pattern-welded sword blades, and they can't handle the pressures of modern ammunition; they explode. What's good for a blade isn't good for a gun or its ammunition.

>>534745

>Steyr ACR

The HK G11 had a similar salvo burst, but when combined with the G11's recoil reduction system, the shooter didn't feel the recoil of the first shot until the third one had already left the barrel. It could place all three bullets from the burst into an area the size of a quarter (greatly enhancing the odds of penetration body armor or light cover); presumably the ACR had similar performance given the almost identical rate of fire of its salvo burst, and the light recoil of the flechettes probably wouldn't differ too much from the recoil of the G11.

But this isn't a rifle firing a rapid burst intended to increase hit probability or penetrate body armor, it's a machine gun with a high rate of SUSTAINED fire. Yes, a forced air cooling system like the Lewis Gun or SITES Spectre M4 would help, but a quick-change barrel is still a must for a machine gun with a high rate of sustained fire. The PKP has a lower rate of fire than the PKM and a thicker barrel for a reason.

I'm imagining something like an MG3 GPMG with three chambers in a revolving cylinder and a quick-change barrel. Use modern super-alloy steel and chrome lining so the barrel lasts longer and doesn't overheat, and quick-change so you can swap barrels every so often. The MG can have a fire rate selector, one setting for a more typical rate of fire and another for "fuck everything as fast as possible", which would be used for shooting at aircraft, vehicles, or just raping everything in sight at the expense of ammo. Or possibly design it so it fires rapid bursts, but extended fire causes it to trip a second position on the sear and reduce the rate of fire to something a little more controllable.

>>533880

Reminder that White Russia is the only sane country in Europe only european country with death penalty, and lowest "freedom of press" rating

We should negotiate with Lukashenko to parition ukraine and create a zoo for ukrainian nationalists (^:

>>534744

I know they used to use Zinc as a substitute for lead in cast bullets when lead wasn't readily available. I'd imagine you could put a thin layer of tin or something around it, or even just use a copper-cobalt alloy instead of a copper-zinc (brass) alloy.

Chemically and physically, Zinc and Cobalt are extremely similar (which is why cobalt poisoning is so common from zinc supplements), but I know Cobalt is more dense, has a higher melting point, has only slightly less thermal conductivity than zinc, and is far less reactive to acid/corrosion than brass is. Additionally cobalt dust can ignite in an oxygen-rich environment, so other than maybe trace carbon being higher than zinc, I'd imagine it'd be self-cleaning. Additionally if I remember right, cobalt produces a very mild magnetic field which would be expanded by the rotation of the boolit plus tumbling. I'm not sure how effective this could be, but they might be able to act as miniature EMPs for signal jamming purposes with a high enough cobalt content.

I was thinking you could make a copper-cobalt or aluminum-copper-cobalt alloy with a thin tin or steel plating that's cheaper than brass so that the brittleness of the cobalt is accounted for while using its hardness to help with penetration, and get some nice side-features out of it that were never intended in the process. Biggest downside is it'd be heavier, but to make up for that the ammo would be far less corrosive and have a much longer shelf life than regular brass would.

>>536339

Zinc is not a substitute for lead in bullets, it's used to alloy with lead to make hard cast bullets that get better penetration, as opposed to soft cast bullets that expand on impact.

Tin isn't the worst; they coat steel cases with tin. But cobalt and zinc are both terrible for casings, given the way they split, flake, etc.

And I don't get the desire to develop some new alloy of aluminum-copper-cobalt or whatever, when brass has been used for centuries because it's perfect for the application.

>>533581

>Aluminum is the most common metallic element on Earth

Actually iron is, but I digress. The issue with aluminum is that it's hard and will crack rather than brass which will bend. You need the case to bend out into the bore to create a positive seal. Aluminum won't do this, and it will best case just cause a lot of propellent to go out around the barrel, worst case break and throw aluminum all throughout the action. Aluminum also has a much higher melting point than brass, meaning it's harder to work with in some circumstances.

>>539899

>Aluminum melting point: 1221°F

>Brass melting point: 1652°F

Element Abundance percent by weight Abundance parts per million by weight

Oxygen 46.1% 461,000

Silicon 28.2% 282,000

Aluminum 8.23% 82,300

Iron 5.63% 56,300

Are you a shitposter?

>>534252

>britkike (1)-and-done proxy samefagging this hard

kill yourself, muslim muttkike

Aluminum and steel crack and break more easily. And I don't know if I'd trust some aluminum shit to handle rifle cartridge pressures.

I like brass because I can reload that shit and get more range time for the money.

>>533769

I thought you posted good shit, for what it's worth.

>clip