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How is an MP5 on at 25 and 100 meters? the MP5 manual says it is and I've seen a vid of some guy doing it, but I can't get any ballistics chart online to show me 9mm hitting at the same spot for 25 and 100 meters
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>>64468376
You point it up more for 100m
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>>64468448
both the manual and the demo I saw said poi was the same for 25 and 100 meters. the vid shows maybe + 2 inches for 50 m and -2 inches for 100 m if that. I think it was still something retarded like -24 inches at 200m and he aimed like 10 feet high for 300 m
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>>64468376
25m is the distance where the arc of the bullet first crosses the sighting plane
since the bullet is traveling in an upwards arc it continues to be high until gravity brings it back down to cross the sighting plane at 100m
most guns have two zero distances like this
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File: 1754705211911591.png (63 KB, 1000x600)
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Maybe this image will help you OP
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>>64468561
>>64468570
I get that and I know it exists for 5.56, but every time I plot it on those different calculators it makes 25 meters like the apex. Like how if you do a 100 yard zero with an AR it doesn't have a second zero point, the bullet just apexes at 100 yards. Or like a 50 yard zero on a .22lr is pretty similar, it just apexes at 50 yards and doesn't have a second zero
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>>64468586
Lol moron, it's a ballistic trajectory, it will ALWAYS have two zeros unless you're sending it into orbit.

Just think about it mathematically, there will always be a near zero and a far zero, with the far zero generally being your "true" zero that you use.

Explain to me how a bullet could EVER have just a single zero unless it's in a zero G environment, or has the muzzle velocity an appreciable percentage of the speed of light.
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>>64468586
>how if you do a 100 yard zero with an AR it doesn't have a second zero point
Does the bullet just keep travelling into space? Lmao what the fuck are you smoking?
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>>64468600
You could zero at the peak of the arc
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>>64468605
mathematically impossible, you'll still have two zeros just incredibly close together.

Even the two zero's are only a few inches apart, they're not in the same place.
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>>64468600
>reddit spacing
>>64468600
>>64468604
holy shit both of you are retards. a 100 m zero is basically the same zero as the 50/200 meter one, the only difference is the 100 meter one zeros on the apex of the parabola. the bullet never goes above 100 meters. that's why acogs use 100 meter zeros. the top of the chevron is the highest point the bullet ever gets to
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>>64468642
Except a 100 meter zero does not in ANYWAY necessitate a "single" zero (and again, it isn't a single zero, you've just moved your two zeros very close together).


At best your two zeros basically overlap, but mathematically, there are still two distinct zero points.


If you want to call that a "single" zero feel free, but looking at the math you'll easily see there are still two distinct zero points.
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>>64468650
even if it has a second zero inches apart, it's not like it makes a distinction that matters at all when shooting.
I think you're just a nogunz
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>>64468668
Sure, but if you zoom in on that line at the 100 yard zero, it's two distinct points in space where it crosses the LOS, not a single point.

The distinction might not matter when shooting, but it does when explaining to OP how a gun can have a "single" zero at 100 yards compared to other guns that have two distinct zeros.

The 100 yard zero ALSO has two, you've just moved them very close together making it effectively "one" zero. But to explain to OP how/why it has a single zero it's better to explain that it IS two zeros, they're just nearly overlapping.
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>>64468642
>the 100 meter one zeros on the apex of the parabola. the bullet never goes above 100 meters. that's why acogs use 100 meter zeros. the top of the chevron is the highest point the bullet ever gets to
Uhhh i'm gonna press X to doubt.
I thought standard 5.56 loadings with a 100 meter zero have a zero at about 15-20 meters, and another zero at around 100 meters, with the apex of the parabola being about 1-1.5" over zero at around 50-60 yards.
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>>64468696
No. Wrong. No, no, no, no

A pure 100 yard zero has the parabola peak of the trajectory at.......
100 yards!
That is the point of impact. The arc's peak is also the point of aim, which is also the point of impact.
There are not two zeros with a pure 100 yard zero.
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>>64468751
Again, even if it's 99.999999 yards and 100.0000001 yards, those are two distinct points in space, even if they're infinitesimally close to each other.

The math doesn't lie bud.
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>>64468696
it doesn't and also who cares reddit spacer. you are being a gay retard and that's not the topic of discussion. we are talking about the parabola for 9mm out of an MP5
>>64468715
if it has a second apex it's at like 75 m
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>>64468614
Kek, ok you win this round mr. asimptote. You could have a practical single zero though. Not sure how actually useful that is for any gun in particular but you could.
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>>64468874
he's not even right, you can zero off a tangent line to the parabola peak
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>>64468882
In a 3D space, using a real firearm, you're never going to be able to do that.

In a computer simulation without real-world constraints, sure. But not in reality.

You will always end up with two zeros even if they're just millimetres apart.
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>>64468889
a. everyone who reddit spaces is a no gunz tranny
b. there is a theoretical maximum of the parabola. if your zero is at the tangent line to the theoretical maximum then you only have one zero
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>>64468889
In the real world, if you zero at the maximum of the parabola, the round will fall slightly below your theoretical zero point as often as it falls slightly above. Does that mean you will always have no zeros? No, obviously. You are not impressing anybody so stop trying to unnecessarily over-complicate a simple topic.
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>>64468924
>>64468901
>>64468586
>Like how if you do a 100 yard zero with an AR it doesn't have a second zero point, the bullet just apexes at 100 yards. Or like a 50 yard zero on a .22lr is pretty similar, it just apexes at 50 yards and doesn't have a second zero
Again, in order to explain to OP how some guns have two and some have one, in reality BOTH have two zeros, just sometimes those two zeros are close enough to EFFECTIVELY be a single zero.

But a 2nd zero still mathematically exists.
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>>64468967
ok, fuck off reddit spacer, you aren't adding anything to the discussion and you have no gunz.
we want to see a parabola for 9mm nato out of an mp5
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>>64469016
It's fine to be retarded OP, nothing to be ashamed about.
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>>64468376
They switched to the p90 for a reason. The anemic 9mm struggled to penetrate jaffa armor.
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>>64469027
that was the armorer being based and autistic and buying P90s without telling anyone because he thought they made more sense in lore and then he brought them to multiple meetings until they asked him about them
>>64469021
nah, you are the gay retard here
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>>64468967
>Again, in order to explain to OP how some guns have two and some have one, in reality BOTH have two zeros, just sometimes those two zeros are close enough to EFFECTIVELY be a single zero.
look dude, even if you are correct, OP was never asking how some guns effectively have one zero, he was asking how an MP5 shooting 9mm could have a 25/100m zero and was talking about how ballistic calculators showed him zeroes where 25m was effectively the apex. you're the only autistic fuckhead who cares about being technically correct about mathematical shit that has no bearing on real life. and you still haven't explained why you can't have a zero at the tangent line to the theoretical maximum.
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>>64468967
No, you're still a moron.
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>>64469027
>TFW your TV show buys up all the available 5.7mm FN blank rounds, really pissing off the Secret Service, and so you switch to other weapons to cause less trouble
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>>64468772
It's called a double root retard. You can have them at the same point.
>>
I need to run highschool level math by you retards more often, watching you guys try to crack that simple nut is fun for me.
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>>64469702
Wormhole Xtreem was a hell of a show.
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>>64470427
I know, right, it's just an insane idea - that the US military would use popular culture as cover for something horrific that it was actually doing . . . . I mean, just imagine a world where that might happen. What a horror show, amirite?

https://www.youtube.com/watch?v=CKrCqnH2Tzg
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>>64469702
Is that a fuckin bump stock...?
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>>64468600
If your first zero is negated by arming distance, you can have a single zero.
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>>64468600
I just zero so the apex is infinitesimally lower than the sight line and that way I have no zeroes but still shoot accurately.
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>>64468561
>>64468570
These are your answer, OP.

>>64469027
5.7mm gets absolutely raped in terminal ballistics AND armor penetration with any half-decent armor piercing load of 9mm. The P90 was chosen because it looked more modern and distinct.

>>64471233
It's a thumbhole stock (which at one point was California compliant I think, but not for very long). The "Carter Special" was an Olympic Arms KB23 carbine with some of these parts:
>ELCAN optic
>Beta drums
>previously mentioned thumbhole stock
>some Bushmaster RIS fore-end which they cut down to fit the gun (and they opted to not refinish the cut surface lol)
This would actually be kind of an awful gun for a number of reasons, but it looked interesting and distinct, and it didn't use their dwindling supply of 5.7mm blanks, so that's why it exists.
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>>64472127
>These are your answer, OP.
I still haven't seen a chart with 9mm ball showing it
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>>64472127
You forgot one extra feature of the Carter Special
>a barrel so short that you'd probably get better ballistics and more energy by actually throwing the bullets at the Jaffa
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>>64472137
They'd be nerfed to fuck for sure, but you'd still get superior terminal ballistics and armor penetration to the P90. Something in the 12.5" to 14.5" range is just a lot more practical (even better terminal ballistics), and wouldn't give you that same SORDID fireball or kablammo with every single shot.
Imagine having to shoot that monster inside of the corridors of one of those Jaffa ships, the sound and concussive blast would be obnoxious as hell.
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>>64472127
>5.7mm gets absolutely raped in terminal ballistics AND armor penetration with any half-decent armor piercing load of 9mm. The P90 was chosen because it looked more modern and distinct.
Yeah citation needed on that one. The 5.7 was at least designed to pierce light armor of russian paratroopers. 9mm wasn't designed to be armor piercing at all and even a version of it with a hardened core is likely to be less good at piercing armor than a smaller, faster bullet like the 5.7 would.
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>>64472144
>Imagine having to shoot that monster inside of the corridors of one of those Jaffa ships, the sound and concussive blast would be obnoxious as hell.
Maybe that was meant to be another signature Samantha Carter, 1300 IQ, move - turn every shot in a confined space into basically its own mini flashbang to disorient the enemy and make them easier to fight?
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>>64468889
Motherfucker. Is your round hitting within six inches on an ipsc sillhouette? Then yoooou are fuuuuuuuucking zeroed dumbass. -2 or -4 or -5 doesnt matter. Its effective hits = 0.

Motherfuckers out there adjusti g zero with 1 inch increments and you wanna argue jewish fucking bullshit millimeters. Begone with your hebrew pilpul nonsense nogunz.
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>>64468376
Are you sure that that zero uses the same setting for the rear drum sight?
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>>64472221
fun fact, the MP5's rearsight drum only has one setting. the drum doesn't change elevation, it's just for how much light you want going though based on personal preferences and ambient lighting conditions. it's like replacing the iris in national match sights
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>>64472226
Well shit, there goes my bright idea
Backup guess: 25m is the true zero and 100m is bull shit
Second backup guess: nato 9mm load for it was pissing hot?
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>>64472231
I can only get the numbers to work if I make 9mm super pissing hot and change the ballistic coefficient but it might be a ball vs hp thing
page 68/69 describes the rear sight and the zero
https://cdn.preterhuman.net/texts/wars_and_weapons/guns/Heckler%20&%20Koch%20MP5%20Submachine%20Gun%20Operator's%20Manual.pdf
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>>64472197
The real 1300IQ move for a 5.56mm weapon to replace a P90 for this would be the Steyr AUG, IMO.

>replace progressive trigger with proper fire selector
>optionally look at replacing the scope with a red dot of some sort
>maybe carry the rifle with one of the 42rd extended mags in it, and then 30rd mags as reloads
>have a handy rifle which mogs the fuck out of the P90 in basically all aspects
>also doesn't deafen or blind you like the Olympic Arms mini carbine does in some circumstances
>could use a shorter 16" or 14.5" barrel to make it even shorter and lighter, and STILL be far better than the P90 and Carter Special
>still looks fairly futuristic by 1990s standards
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>>64472215
>he doesn't understand basic math
Oof, many such cases



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