Thread 64154472

if someone in the USA started manufacturing 5.8x42mm AR's, along with ammo, how successful would it be?

theres a cult following for 5.45; but for what its worth, 5.8 is theoretically better than both 5.56 & 5.45, so wouldn't that give it a leg up?
to try and even out the hypothetical, lets say it all costs the same as 5.56 rifles & ammo (nobody is gonna buy something expensive)

inb4 chinkshill
nigger, its a fucking cartridge that isn't even allowed for export out of china

>>64154472 (OP)
>how successful would it be
>5.8 is theoretically better than both 5.56 & 5.45, so wouldn't that give it a leg up?

It would be shit if using domestic chinese spec manufacturing. Otherwise it is reaching the point where something slightly more American would be better anyways. 6.5 would be a better choice.

I doubt it would be popular, 556 is only popular because it is used by the government and militaries worldwide. It is optimized for human targets, shit like hogs are also prime targets. 556 is otherwise too anemic for humane hunting, and I doubt 5.8 would be all that much better.

>>64154472 (OP)
the only way it would catch on is if we could get QBZ-95's imported. and even then the QBZ-97 would be more popular.

>>64154472 (OP)
>theoretically better
In what ways?

I would buy all of it

>>64154472 (OP)
>theoretically better
That's not enough for most people

>>64154472 (OP)
If we got the chinkpup that the leafs get it'd probably get a following but they also make them in 5.56

>>64154529
just some more taper, powder volume, and projectile length
its like how the soviets saw the 5.56, then adopted a modified form of it a decade after with some more experience
the chinks adopted 5.8 about another 5 years off the soviets, so it basically goes in a line of improvements from 5.56 > 5.45 > 5.8
its more similar to 5.56 than 5.45 too, its an interesting cartridge

>5.8 is theoretically better than 5.56 and 5.45

theoretically, maybe. It’s far too similar to 5.56 to warrant rechambering any existing guns, other than for the novelty factor of being able to say you have a 5.8 gun.

>>64154472 (OP)
The one and only compelling feature of the 5.8 is the dual OAL specs. It's neat, but pointless in the way they implemented it. Their machine guns and DMRs should use a more powerful cartridge instead of a longer one. Shortened pistol loads of an intermediate rifle cartridge would be much more interesting.

>>64154472 (OP)
>5.8×42mm
>5.56
>5.45
All of that is old news. 6mm ARC is where it's at. The Russians know it too; that's why they made 6.02x41mm.

>>64154643
^^^ this man knows what hes talking about

No one wants high velocity small bullet anymore, we're entering the age of suppressors on every gun where larger subsonic calibers make more sense.

>>64154472 (OP)
> looks like shitty ballistic coefficient.
I doubt it outperforms 6mm ARC.

>>64154758
sometimes you want to shoot past 150Y.
If you're shooting suppressed +supersonic then might as well jump up to 6.5 creedmore and touch targets at 1000Y with ease.

>>64154758
For who? Subsonic have terrible ballistics and penetration. There is no military using subsonics for their primary rifles for this reason. They only really make sense for spec ops type units.

>>64154758
holy shit are you that .300 schizo?

It's time to bring back the 7.62x45mm cartridge!

>>64154782
90% of the US population (everyone living in a city, or in a suburb in the eastern part of the country, or forested coastal region) can't realistically get over 100 yards without driving to a dedicated range thougheverbeit
>>64154794
>for who
People who shoot for fun? Small arms are obsolete for militaries anyway, drones clearly won that one.
>>64154807
No, not a fan of it, I think 458 Socom makes sense though

5.7 is just better cuh

>>64154832
5.7 is smaller than 5.8, so no
they should make a 5.9, that would be best

>>64154834
I stand corrected

>>64154472 (OP)
We have 6.8 SPC II which is considerably better than all 3 of those, and it's not selling.
If we didn't have retarded import laws from Bush 2 and Clinton, we'd have 5.8 rifles from Polytech/Norinco.

>>64154824
>No, not a fan of it
Not a fan of .300 BLK, eh. How do you feel about .338 ARC?

>>64154852
> We have 6.8 SPC II which is considerably better than all 3 of those, and it's not selling

Well why do you think that is? Respond in a serious manner please, nothing like “because the entire world is retarded”

>>64154852
>6.8 SPC II
The original 6.8 SPC died because its performance was worse than 6.5 Grendel. How does this SPC II hold up against its 6.5 competitor?

>>64154855
Okay, here's your answer: Nobody wants a Chinese round unless we can get it imported FROM CHINA for CHEAP.
We already make 5.56 at considerable volume which is why civvies can get it so cheap.
The reason the 6.8 SPC II isn't more popular despite being widely adopted is that it's expensive.
Nobody is going to buy a gun with ammo that costs 3x as much and has no real benefit, or they would have bought it in 6.8 SPC II already, and, spoiler alert, no.

>>64154871
cartridge is narrower and you can fit more in a magazine. It doesn't have some fucking wobbly ass profile. It's delivers about 44% more energy than a 5.56 while being only slightly larger.

>>64154879
>cartridge is narrower and you can fit more in a magazine.
Okay internal ballistics are more impressive; you're not going to impress the free market unless the external ballistics and terminal ballistics are also better than the 6.5 Grendel's.
>It's delivers about 44% more energy than a 5.56
Couldn't care less about how it performs against 5.56 because 5.56 addicts are not the ones buying these niche rounds; that's why I brought up how 6.5 Grendel beat 6.8 SPC the first time around.

>>64154824
If you're just shooting for fun caliber and ballistics is irrelevant anyway. Subsonic 9mm is going to be way cheaper. Or fuck it 22lr is pretty quiet and can be had for pennies.

>Small arms are obsolete for militaries anyway, drones clearly won that one.
Thats why every military still uses them including the ones in Ukraine. Drones become much more limited when you start facing EW. You basically are limited to flying around everywhere with a fiber optic cable. Same reason why you won't see robot soldiers until you can completely automate away the targeting/human aspect.

>458 SOCOM makes sense though
Maybe for larping

>>64154886
Who are you selling these to? Because the "people buying your niche round which fulfills the role of several already established products on the market" are going to care.
Why do you ewwant to introduce this round, what does it do better, who is going to buy this?
Then you have to worry about volume manufacturers who would already be making these if they were financially viable.

>>64154561
is there a mathematical function that can be optimized for dimensions that produce "more gooder"? How do they come up with the exact numbers of the dimensions?

>>64154886
6.5 Grendel can't be safely used in a standard AR-15, though. And if you're going to build a meme gun with a custom bolt, barrel and receiver, you should go all the way to WSSM.

>>64154905
>How do they come up with the exact numbers of the dimensions?
by measuring & shooting them

functionally, its essentially identical to 5.56, its just that the length of the round makes it have both a better ballistic coefficient & penetration
the other, legitimate benefit, is that you're able to fit more technology into the projectile on account of the added length, like tungsten cores & expansion cavities
the larger case volume allows more techniques regarding powder too, so you can get better burn rates & higher pressures

has someone made an AR chambered in 5.45?

>>64154900
This would have been a great response to the guy I was talking to. The one who is fanboying over SPC II. I'm not even trying to attack him; I just don't understand why anyone would honestly give 6.8 SPC II a second glance. It honestly looks like worthless garbage on paper.

Depends what you want to optimize for?

If we're talking about purely ballistics i.e. minimizing loss of energy over distance, you need to maximize mass and minimize drag. (Modeling drag in a fluid is a very common engineering problem with lots and lots of math that will put you to sleep). But typically a longer skinnier bullet is better.

The counterpoint is if you make it too long and skinny its hard for the rifling to spin it fast enough to stabilize it and keep it from tumbling sideways, destroying your accuracy. You can increase the twist rate of the barrel to compensate, and this is why many "long range" cartridges like 6.5creed have faster twist rates but shorter barrel lifes than more traditional rifle cartridges like say .308

Everything has tradeoffs so you need to know what you're optimizing for.

This is also why pistol bullets are short compared to rifle bullets because the range they are expected to be used at and barrel time to stabilize them is shorter.

>>64154989
>This is also why pistol bullets are short compared to rifle bullets
yes, i'm sure thats the reason, and has nothing to do with the red line on this image

>>64154982
The point I was trying to make is that it exists, it already fills that niche, 300 blackout already fills that niche, what are you bringing to the table here that several other cartridges don't already bring? Also, you'll be building tooling and everything else from the ground up, new bolts and barrels, developing the gas system if these are AR drop-in parts, new magazines, when several competing products already exist on the market.
The only way i can ever see 5.8 being popular is
WW3 happens, China gets massively humbled, people bring back rifles somehow or China's industries are set up to generate revenue, a president unbans Chinese imports, we get some post-Soviet economy trying to get back on its feet scenario where we can get billions of these rounds for 40cpr, and Norinco/Polytech make civvie market offerings for hunting and whatever.

>>64154993
>yes, i'm sure thats the reason, and has nothing to do with the red line on this image
NTA but you don't have to use an autoloading pistol. Revolving pistols exist and can take cartridges with longer overall length.

>>64155021
which ends up with you having either an anemically short or an overly long barrel

>>64155026
>overly long barrel
No such thing.

>>64155026
>>64154993

I mean even humble 38spl is much longer case than 9mm but has a similar bullet size/shape/mass despite the fact with modern powders you could in theory use a much longer bullet and give up some casing space for the same pressure as 9mm.

The point is length relative to diameter, you could scale a rifle bullet down to fit in a handgun form factor and get much better drag resistance but its a retarded idea.

You lose too much mass, which at the lower velocity of a handgun negates any gains you would get from reducing drag, so you still have shit BC. On top of that with less mass brings shit lethality. This is why nobody makes serious handgun cartridges below .22/5.7 even if in theory putting enough energy and velocity behind them could make them fairly lethal.

>>64154993
NTA. Is that red line meant to illustrate grip angle? Or the obvious observation that pistols feed through the grip?

Pistol bullets are short A) because the necessity to feed through the grip imposes severe dimensional constraints on the cartridge, and B) like that other anon said, since pistols are short ranged guns, there is never gonna be more like 50 yards of atmosphere between you and the guy you’re shooting, so BC can sacrificed will no ill effects.

If your bullet has a BC of x, and energy of y at z yards, doubling BC gives you y energy at 2z yards. So if a sensible BC for 300 yards is, let’s say 0.18G7, then a sensible BC for 50 yards is 0.03G7. that’s just 0.18*(50/300)

All this to say that it wouldn’t actually matter if the pistol’s mag was placed outside the grip, because if the max range of the pistol is still around 50 yards, then BC still isn’t gonna matter, so you’d stand to gain nothing inside 50 yards by increasing bullet length, notwithstanding higher SD, deeper penetration, wider expansion, etc.

>>64154989
Here is an invaluable online resource another anon informed me of for modeling bullets and their BC/form factor.

http://www.geoffrey-kolbe.com/cgi-bin/drag_working.cgi?unit_length=mm.&weight_unit=grains&bullet_name=Custom+bullet&re_calculate=yes&boundary_layer=L%2FT&diameter=10&length=50&nose=30&meplat=1&drive_band=10&base_diameter=8.15&angle=7.5&boat_tail=7&secant_radius=20.5&weight=324.9&density=8.5

(If you’re changing boat tail length/angle, make sure to clear the “base diameter” field first.)

Kinda wish it could model other nose geometries, but the only option is a radiused ogive.

>>64154472 (OP)
Why is theoretically better? Genuine question.

>>64154989
Here’s a better link

http://www.geoffrey-kolbe.com/drag.htm

>>64155107
Theoretically better for what? You need some metric to define better by. For military use? Sacrifice a few million conscripts in live tests and find out, otherwise your guess is as good as the governments.

Entire dozens of people would be eager to try out 5.8.
5.45 having as much of a following as it does is from cheap milsurp getting its foot in the door.

>>64154472 (OP)
Dead in the water unless it was insanely cheaper, which wouldn't be possible unless you import in en mass, which itself is also impossible. There is no cult following for 5.45. it was only successful when 7n6 was importable for 11cpr. It is now dead in the US aside from AK74 owners.

>>64154472 (OP)
I've shot 5.8, if we're talking just chang ammo, which would be the only benefit from this and they don't even export it, it's fucking atrocious. Shit will probably give your lung cancer cancer, whatever propellant and primer they use shit is the most acrid, worst smelling powder there is, and you bet your ass it's got a corrosive primer with a healthy dose of mercury. Only shot it out to like 200 yd so I can't speak for the accuracy, especially since I shot it out of a QBU-88, and full auto out of a QBZ-95 didn't feel all too different from 5.56. Peformancewise, there's a gazillion other meme cartridges to pick from that perform better than it in some way shape or form. 0 reason to ever chamber a gun in it in the US.

>>64155273
>"I've shot 5.8"
ok nogunz

Are there any posters in this topic,
that have experience, usage of any firearm chambered in the OP cartridge?

>>64155273
not surprising that is basically just a 1-1 of 5.56, its the whole point of the cartridge after all
cool to hear about it though, especially of the QBU-88, didn't even know that was a thing
>>64155328
you could have at least asked what country the guy is, retard

>>64155273
It’s incredible that we split the atom, invented transistors, put a supercomputer in everyone’s pocket, and landed on the moon, but we haven’t figured out how to keep a gun from poisoning it’s user with heavy metals. Absurd. Where are our priorities?

>>64155384
>but we haven’t figured out how to keep a gun from poisoning it’s user with heavy metals.
yeah, heavy metals are overrated, hydrazine is where its at!

>>64155342
>you could have at least asked what country the guy is, retard
people lie about shit on /k/ all the fucking time because they think it will somehow make them cooler for 15 minutes.
There are like 10 people on /k/ who actually own guns and I'm at least 3 of those people.

>>64155328
There are a gazillion different intermediate cartridges a little bigger than 5.56 out there -- all recently designed by experienced ballisticians stateside and manufactured to vastly higher civilian standards -- that would be a little better than a cartridge a third world military made in the 1970s mostly to solve the issue of people stealing ammo and selling it outside the country. They don't sell because they don't offer that much of an improvement compared to the logistical effort required to make them affordable. There are a lot of new and highly competitive 5.56 loadings anyway, it's not *inherently* much worse really.

>>64155396
why does every single person who says "nobody owns guns but me!" never posts guns as they say that?
you do realize how empty your statement is when doing so? (or should i say "not" doing so?)

>>64155405
because this thread isn't about my guns and that would be off topic.
lurk moar faggot

>>64155408
the thread isn't about you claiming nobody owns guns either, noguns

>>64154529
>>theoretically better
>In what ways?

Longer, more streamlined bullet with better ballistic coefficient. Americans have never been good with advanced bullet designs. F.ex german-spanish CETME 7.92x40 cartridge with low density bullet mogs both x39 and x51 and that was 75 years ago.

>>64155410
it is now. checkmate, atheist.

>>64155384
Isn't the risk mainly due to the materials in primers? I've advocated for electronically fired (electrically primed) polymer cased-telescoped cartridges for too fucking long now. The technology has been there since the 80s at the latest, .mil just keeps killing it for some reason and civilians won't adopt it first due to commercial and legal risks (Remington EtronX).

>>64155420
we have primers that are perfectly fine, its just cheapo dogshit ones that'll get you
the bigger danger is the gasses from the powder

>>64155412
I was gonna lol at you for making a big deal out of an extra 0.1 caliber in ogive length, but desu you’re right. 2.633 calibers of ogive length vs 2.23 calibers for the 5.56. It’s not nothing. And they’re using a 77gr bullet with an SD of 0.19lb/in^2. The BC is gonna be in the range of 0.175-0.190, plus it starts with more muzzle energy. Honestly not bad, but also not better by a significant enough margin to warrant introducing this new cartridge.

Also, 6mm max is basically just 5.8x42 except better, so there’s that.

CAPTCHA: KKKA0

>>64154472 (OP)
yes we need another meme cartridge with proprietary mags and bolts
224 valkyrie
22 arc
25 45 sharps
are all so successful

>>64155495
every single gun should be its own caliber, even between serial numbers of the same model of rifle

>>64155500
You need to be in jail for suggesting this. I don’t care if it’s a joke. You don’t joke like that.

>>64154758
No, the future is cartridges balanced to have excellent sub and supersonic performance compared to say 5.56 which is excellent super but worthless sub. Seeing as <6mm is the ideal for zippy projectiles and >7mm is good for fat subsonics I think the cartridge of the future is somewhere in the 6.5 range

>>64155536
Subs are a meme in a military setting. Maybe super secret ninja subsonic stuff, but beyond that, subs don’t matter. I get that you like them, I think they’re cool too, but no, some 6.5 version of 300 blackout is not the future of service rifle cartridges.

>>64155584
Oh for sure, I'm more talking about civilian use since with the NFA tax going away I forsee suppressors becoming more common and there evolving a need for 1 round that can satisfy both the quiet and loud shooter crowds. At least I'd like something that could scratch both itches, it'd be nicer than having a dedicated quiet gun

>>64154561
China adopted 5.8 so there wouldn't be any market for corrupt military officials to sell their ammo to. Their entire small arms family was just Russian designs, there was no reason to make their own cartridge, except they can't trust people to not steal it

>>64155145
Love that edit

>>64155396
You're also probably the only three out of those ten that actually shoot said guns

>>64154472 (OP)
All of the data on this round is out of something retarded like a 24" lmg barrel and they compare it to a 14.5" barrel m4. Plus there's wildly different loadings in existence and that's not even accounting for Chinese fluffing.

Don't get me wrong id love a 181 or 03 in the cartridge but it wouldn't be more than a novelty. 5.45 has way more appeal to me and I think most others too.

>>64154966
Adams Arms made a 5.45 upper. Shame the mags were made by c-products.

>>64154989
>This is also why pistol bullets are short compared to rifle bullets because the range they are expected to be used at and barrel time to stabilize them is shorter.
Actually, you can impart enough spin to stabilize a bullet, even 6.5 sneedmore, with an inch of barrel. The angle of the rifling of what matters, once the bullet starts spinning it doesn't stop spinning if it comes out of the barrel too soon.

>>64155500
integrate an AI chip into every gun to measure the typical performance characteristics and range data and use an algorithm to determine the optimal cartridge design for each individual user, supplied by our post scarcity nanotech fabricators!!!

>>64157690
>we have hyper advanced millionth-gen AI
>we have nanotech fabricators
>…
>still killing by throwing rocks

>>64154472 (OP)
fuck you chang and your keyholing knockoff round
Now desperately reply on the wall of smartphones made in korea to say no u

>theoretically better
3% here and 3% there is practically the same when it comes to cartridges. Waste of time to consider. Stupid to claim theoreticals

>>64159439
I don't think OP is a chang, just kind of dumb.

>>64159439
man, i fucking wish the chinks would pay me with a CS/LM4 to shill, shit would be cool to play with
>>64159463
i'd say i'm as dumb as the current cartridge manufacturers, coming out with ten different forms of 6.5 creedmoor clones (very, i am very dumb)

>>64159471
> i'd say i'm as dumb as the current cartridge manufacturers

Impossible. Their stupidity can not be matched. 22 sneed, 24 sneed, 25 sneed, 26 sneed. I bet they’re seething and red in the face because there is no standard .23X bore.

>>64155328
They used to have firing ranges in changland where they let you try out all sorts of different guns. They were open for foreigners when I went. I had a load of fun shooting DShKs, chang firearms and they even had a HK33.