/k/ - Weapons

>>329808

While .45ACP CAN get close to the numbers produced by 9x39mm, the ammo that the US military uses doesn't even come close.

I believe this niche is one of the contexts in which 300 Blackout is always discussed. However, it's unlikely that it will ever be adopted by US forces any time soon.

>>329817

.300 Blackout is closer to 7.62x39 in ballistics.

9x39mm surpasses that.

Subsonic .45acp has energy values within 83-90% of 9x39mm.

In comparison the 9x39 is a narrower, longer round with better balistics in flight, giving it better effective range. Too, it is designed to penetrate up to 10mm steel plate, which I doubt the .45 loads could manage.

Also just as a side FYI, the Russians have since replaced the 9x39mm with 12.7x55mm.

The 12.7x55mm subsonic is a 1111 grain bullet fired at a speed of 314m/s giving six times the energy of a supersonic .45ACP, two times the energy of a supersonic 5.56mm, or slightly more energy than supersonic 7.62 NATO.

>>329817

9x39 is far superior to .300 blackout.

>>329836

I guess the West did invent .50 beowulf and .458 SOCOM.

>>329808

the thing about that round is it goes hand-in-hand with the rifle that uses it, and the west doesn't really have anything in that niche.

There's rare and proprietary stuff like .300 whisper people use, but overall it's not part of american military doctrine, and doesn't fill too large of a civilian niche.

>>329839

Russians tend to exaggerate the potency of their cartridges a tad, take it with a grain of salt.

>>330040

>exaggerate

The military-grade high power .223 ammunition that literally blows the arms off of innocent schoolchildren

>>330107

>innocent schoolchildren

That's more a media thing. With 5.56 it was "muh fragmentation increasing the lethality by ten-folds".

>>329817

>While .45ACP CAN get close to the numbers produced by 9x39mm, the ammo that the US military uses doesn't even come close.

Only at point-blank/extremely short distances, .45 has shit ballistic coefficient and awful sectional density, so it loses speed due to air drag and suffers more drop and wind drift than a rifle round like 9x39 (which has a nice boat-tail design). And lets not even mention the lack of tungsten or even a steel penetrator to make it more effective against armored targets.

>.300niggersout

It's 7.62x39 with slightly better ballistics and more bullets to chose from. It also has less cartridge capacity than 7.62x39, so manual reloading of the later with 7.62x54r bullets should let you surpass the max performance you could possibly get with .300blk.

>>329842

>.458 SOCOM

I always found that cartridge to be very interesting. If I was on the states I'd probably build a rifle for it

>>330040

>Russians tend to exaggerate the potency of their cartridges

No they don't.

I've never heard of this bullshit, where are you getting it from?

>>330142

Rumors and allegations, amirite?

Still, the claims about 9x39 seem to be reasonable. Can't say much about 12.7x55 other than being inefficient as a general propose round, but very interesting for SF due to its versatility. I'm not sure if it ever catch on.

>>330142

>Canadian

>doesn't know when people are exaggerating

>can't tell when people are straight up laying to him

>probably still leaves his doors unlocked>>330142

>>330142

I just remember browsing russian sites where they talk about how their new 9x18 mak round will pierce Level III body armor. I'd believe there's a variety of sources or some miscommunication going on, but I'm just saying take military information from all countries with a grain of salt.

>>330168

>I just remember browsing russian sites where they talk about how their new 9x18 mak round will pierce Level III body armor. I

pretty sure you mean 9x19 7N31/7N21

>>330168

You're probably misremembering the 9mm para overpressure variants.

>>330168

>I just remember browsing russian sites

If it was some forum, don't even waste your time, Russian weapon forums are pure cancer 99% of the time, even with the shitty translator you can tell they have no idea what they are talking about.

Still, I believe >>330171 and >>330173 are right, it was probably talking about the +P+ 9x19mm round with polyurethane coated penetrator. They were also probably talking about Type IIIA (the top dog of pistol round armors), type III can stop rifle rounds and I really don't think any reasonable pistol round can do shit against it.

>>329836

>9x39 is far superior to .300 blackout.

In which way(s)?

>>330306

>Piercing titanium at 500m

>Big fat boolit ruins everything

>>330306

Carries more energy, pierces more armor, more stable in flight.

>>330186

>If it was some forum, don't even waste your time, Russian weapon forums are pure cancer 99% of the time

How? Intense shilling, or it's just full of сука?

>>330306

Well, when it comes to subsonic shooting, you're working with one -somewhat- fixed variable: Muzzle velocity.

The limit after which the fired bullet produces a sonic boom sits around the 1000-1020 FPS mark, this can vary depending on environmental factors such atmospheric pressure, temperature and more; precisely because of this, 9x39 was meant to run at somewhere around 920-960 ft/s out of a VSS, to leave a safety margin in case the environmental conditions were favorable for an earlier sonic boom.

Since velocity is capped we are left with two main variables to play with in order to get the best performance and energy down range: That's weight and Ballistic Coefficient.

.300niggersout is pretty much a 5.56/.223 case cut and expanded/necked up to fit a .309 bullets (commercial .300blk cases aren't like that, but the end result is exactly the same). The case has less capacity than 7.62x39/9x39 cases and the optimal subsonic performance its achieved with 210-220 gr bullets, solid lead casted bullets can go as far as 230gr before speeds starts to suffer (given the right barrel length).

The weight on the Russian round sits at 267 gr with a tungsten penetrator. So that's more weight weight (and energy) with the added benefit of being capable of penetrating harder armor.

The BC is a bit more complicated. First of all, we don't have very solid numbers on 9x39, I could run a full simulation with the appropriate drag coefficient and whatnot, but I'd need to have all the detailed measurements specifications and I can't seem to find that infograph with all the details of the projectile itself right now.

Speed also plays a huge role on the BC performance of bullets; The BC you get above 2000 ft/s is not the same you get near to 1000 ft/s.

If I recall correctly the G7 BC on subsonic speed 9x39 was pretty high, something like twice the amount of some heavy boat-tail .308 (which wasn't design with subsonic performance in mind).

The comparison is a bit unfair, you're putting a very task specific and bigger cartridge to compete with a mix-and-match cartridge made with the compromise of being AR15 friendly (no need for bolt change and mag compatibility were critical for the commercial success of .300niggersout).

>>330358

COD kids. At least the ones I went to.

>>330361

BC is essentially sectional density of an object moving in air. The 9x39 BC should be slightly better than .308 but that doesn't matter because at close to subsonic speeds BC is of very low importance in energy loss.

This is why blunt nose or parachute-shaped hollow point handgun bullets are acceptable, despite their BC being 0.1. A flechette round has BC approaching 1, but fire a flechette at close to subsonic speeds and its not going to matter because air resistance doesn't play a part.

In fact unless the BC is 0 a subsonic projectile is likely going to hit the ground before air starts acting on it. This is true even for buckshot, which has a BC of 0.01.

tl;dr At low speeds, almost no energy is lost to air resistance. Far more important is the effect of centripetal force, meaning the wider and the faster the bullet spins, the more stable it is.