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realistic ballistic curves, projectile speeds and loosing energy until point of impact
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Description

Hello guys,

I would like to request a change in the ballistics of any projectile. with this comes the damage that can occur to objects, through body armor, helmets, generally armor, players health.

a rifle projectile becomes faster and travels with more energy the more it leaves out of barrel, up to a certain point, like half of the typically accurately used distance. therefore you have worse wounds when you are "further" away from the shooter, instead of standing directly in front of him.

a pistol ( same as submachineguns, which use pistol ammo ) projectile on the other hand looses power and speed when it leaves the barrel.
that is because these different types use different powders.

This will affect, especially, armor, body armor, helmets a lot more realistically.

Details

Legacy ID
1737867560
Severity
Minor
Resolution
Suspended
Reproducibility
Have Not Tried
Category
Config
Additional Information

I would be more than happy to do researches to help you out with accurate information about this request.

Event Timeline

kOepi edited Steps To Reproduce. (Show Details)Mar 26 2013, 11:00 PM
kOepi edited Additional Information. (Show Details)
kOepi set Category to Config.
kOepi set Reproducibility to Have Not Tried.
kOepi set Severity to Minor.
kOepi set Resolution to Suspended.
kOepi set Legacy ID to 1737867560.May 7 2016, 1:10 PM
kOepi added a subscriber: kOepi.May 7 2016, 1:10 PM
kOepi added a comment.Mar 27 2013, 6:44 PM

I need to correct myself, the reason for the 5.56 to be more effective on ranges further than 50 meters is the yaw/tumbling effect and not the slowly burning powder.
additionally both cartridge drop energy and speed when leaving the barrel, but the fast burning pistol cartridge powder drops far earlier than a rifle cartridge with slow burning powder.
The reason for this is only the barrel length, the different powders only help to maximise the giveaway of energy to the bullet before it leaves the barrel.

in this document you see how much the different cartridges loose power over distance :

http://www.dtic.mil/ndia/2010armament/WednesdayLandmarkBAnthonyWilliams.pdf

100% with you

It would be nice, finally, to find a game where you have to know how your weapon works (I didn't mean know the specifics, but know... "ok, I've this weapon, with this optic... the target is at this distance, I've to aim...." or didn't engage some fights if I know that the distance would give me a disadvantage)

Yes, vote up for me

--> sorry for the possibles errors

Since real ballistics already are in the game (although the engine doesn't go as deep as making tumbling effects different depending on projectile speed and what kind of surface is hit), I think this ticket can be closed.

Balistics need to be improved.

Zombo added a subscriber: Zombo.May 7 2016, 1:10 PM

before changing minor affects of bullet speed on distance, which really only matter because of tumbling effects or directly piercing shots, they should fix the soldiers first, which can suffer a too great pounding before dropping, and maybe add realistic bullet penetration and maybe (though this will never happen with the arma engine) buildings that can partially collapse realistically

i think bullet physics are up to a point where further realism becomes unnoticeable, unless firing a high powered sniper rifle from 50m versus 900m

mybe bigger flaws of the game should be prioritized

kOepi added a comment.Mar 31 2013, 9:56 PM

@Zombo

this thread is essential for other things, I dont care about tumbling.
there is no point in changing the soldier first when there is not even an energy difference within different ranges.

this thread is aiming mainly for body armor / armor, to have realistic body armor you need to have realistic energies hitting it.
I hope you get my point now.

Absolutely!

This would be one the single-most impressive features of ARMA 3. There was a little test I did to prove an opinion I had (which I was wrong about) http://feedback.arma3.com/view.php?id=5650 where I tested (a very approx test) the bullet velocity, I did not take any care in the drop of the bullet just the speed. It was determined that the bullets stay at one speed and they were too slow to compare to real life.

So if the bullets (each calibre different) started at their muzzle velocity at whatever.. 3000 fps, then slowed to a non-lethal velocity against body armor (at that point the arc on the bullet would be gigantic and the range would be huge).

Whatever, good post! I agree!

Bohemia added a subscriber: Bohemia.May 7 2016, 1:10 PM

impressive? not really. seems like a pointless minute detail that will make zero difference. if i shoot a guy at close range, it isn't going to kill him less.

Maxyz added a subscriber: Maxyz.May 7 2016, 1:10 PM

Bullets already drop altitude and lose killing power over distance - what else do you need, kOepi?

kOepi added a comment.Apr 1 2013, 9:30 AM

@johncage
what kind of ppl do you "shoot"? civilians?
or why are they with you only in close range?

even if you were shooting civilians at close range, depending on your pistol and the affected body armor, it can make a difference between life and death.

You guys seem to be under the mistaken impression that the ballistics model is not accurate, but it is in fact quite good. Bullets DO lose velocity as they travel, and each projectile has its own wind resistance coefficient (somewhat of a fudge factor I think, since they don't seem to have individual masses). Bullets ARE less effective at long range than at close range, and it does take time for a bullet to travel. Currently, the 6.5mm and 7.62x45 rounds are set with initial speeds of 795 m/s. By the time the 6.5 reaches a target 1km away, its speed has dropped to about 300 m/s. You can see this change in speed over distance for yourself with the script I'm including below. Simply create a mission with a rifleman or marksman (your preference) and paste it into the unit's init box:

GunHandler = player addeventhandler ["Fired",
{
_this spawn
{

		_bullet = _this select 6;
		_initSpeed = -1;
		_speed = 0;
		while {alive _bullet} do 
		{
			_velocity = velocity _bullet;
			if (_initSpeed == -1) then {_initSpeed = sqrt ((_velocity select 0)^2 + (_velocity select 1)^2 +(_velocity select 2)^2);};
			_speed = sqrt ((_velocity select 0)^2 + (_velocity select 1)^2 +(_velocity select 2)^2);
			player sideChat format["Initial Speed: %1 Current Speed: %2",_initSpeed,_speed];
		};

};
}];

As far as I know, the only major ballistics element that has not yet been incorporated is the effect of wind on the bullet. Other than that, it's quite a good model. This ticket probably ought to be closed.

kOepi added a comment.Apr 9 2013, 8:55 PM

thank you traxusIV, very informative.

nsKb added a subscriber: nsKb.May 7 2016, 1:10 PM
nsKb added a comment.Apr 14 2013, 5:52 PM

TraxusIV, unless the barrel length is under 16" 300m/s at 1000m for a 6.5mm seems a little low. I'm assuming that the 6.5mm in the game is a derivative of the 6mm PPC (which makes sense). At 1000m out of a 16" barrel I would expect the round to still be supersonic.

zGuba added a subscriber: zGuba.May 7 2016, 1:10 PM

Speed of sound at STP is about 340 m/s. Grendel linked above is at 190 m/s at 1000 m.

nsKb added a comment.Apr 17 2013, 5:45 PM

Yeah out of a 14.5" barrel with a 108 grain projectile. That kinda defeats the purpose of the 6.5 Grendel.

kOepi added a comment.Apr 17 2013, 6:39 PM

@nsKb
I dont understand why a 14.5" barrel would defeat its purpose.

in my link a 123 gr- projectile has a power of like 400 ft/ lbs, which equals a velocity of 368 m/s = supersonic. But shot out of an 20" barrel.

nsKb added a comment.Apr 17 2013, 10:39 PM

The 108g projectile defeats the purpose.

nmihaiv added a subscriber: nmihaiv.May 7 2016, 1:11 PM

I would agree with Traxus, the only thing that needs to be added is the wind effect on a bullet.

kOepi added a comment.Sep 23 2013, 3:59 PM

showing some activity

Nicolii added a subscriber: Nicolii.May 7 2016, 1:11 PM

Although I think wind affecting a bullet would be good, it would also be bad.

Wind is something that we feel with our skin and hair. You don't have that constant kinetic feedback and being able to approximate how strong the wind is and what direction it's going, not only that but I've noticed plenty of times when throwing a smoke grenade that the wind in the game changes, a lot, in fact far too much. The most common time I see wind being so volatile with it's speed and direction is normally around dawn and dusk.

I'm perfectly fine with the wind affecting the bullets being left out of vanilla Arma 3. I'll wait for ACE mod to implement it and add in the additional wind measuring instruments for my sniper missions.

If you could explain to me why a bullet gains speed after it left the barrel, you won't mind me stealing your idea for the real world.

The ballistic system in ArmA is pretty good, but not the external ballistics is what buggers me. They are pretty good, if wind would be more of an influence. It is the internal and terminal ballistics that needs alot of love.

Speed != Energy. Mass and speed is where the energy comes from.

Ekin= 1/2mv^2

And the table zGuba posted shows that the M855 barely has enough energy @1000m for fatal injuries. 80 Joule of terminal energy are required for an unprotected human to be killed, 530 Joule for a protected infantryman.

A 77grain Mk262 round retains more energy over distance and is currently used by many soldiers in the field to tackle the issues with the M855 ball ammunition.

The 6.5 Grendel has pros/cons. The magazine capacity is reduced due to the larger cartridge size and the weapon has to be rebarreled, which is always an issue with GI weapons (hence the Army still uses M16 variants).

Terminal ballistics are difficult to simulate, same goes fore internal ballistics. If the projectile has enough energy on impact, only three factors should be considered: Where did the bullet hit? Is there enough energy (and sectional density) to penetrate? Is enough energy retained to kill the target?

Internal ballistics have to take into account barrel length, twist rate (stabilizing factor) and powder mass. Let's count the muzzle to the internal ballistics and the muzzle velocity would also be considered to this category.

As it is in OFP and ArmA games, the ammo has specification in the config as well as the weapon. This is the worst idea, as the cartridge does not inherit accuracy per se or muzzle velocity. It only contains a given amount of propellant and a specific projectile (ballistic coefficient) that factor into the equation.

The barrel is where the magic happens. The twist rate defines how stable the projectile can be shot, a heavy/long projectile generally requires short twist rates to stabilize the bullet (eg. 1:10 for heavy .30 cals and 1:12 for lighter projectiles). The muzzle velocity depends on the barrel length up to a certain length. A .30 only requires 22-24" barrel length, longer bbl do not increase accuracy or velocity.

This leads to a system where the ammo should inherit a basic v0, for a standard barrel length, let's say 14,5" for 5,56x45. The weapon has a factor for the barrel length, the longer the higher the v0 (limitations as aforementioned), shorter barrels lower v0 and larger muzzle flash due to unburnt powder. Recoil also is affected by barrel length, not just by weight.

There is so much about weapons that are not though about in most games, that I can't tell if there is any agenda for ArmA 3 to correct some of the mistakes, as it already lacks basic realism features and the developers don't seem to care.

@ Predator

in the first post I corrected myself.

Noted. Now I need to find another ground breaking invention :D

Ballistics can be fun. And even games like Battleground Europe managed to implement them. But the ArmA 3 engine has about the same "realism" potential as OFP back in 2001 it seems. Or at least the same issues are transcripted from sequal to sequal.

Goose added a subscriber: Goose.May 7 2016, 1:11 PM
Goose added a comment.Dec 3 2013, 5:32 PM

First of all the game already has "realistic" ballistics, to an extent.

Second the ticket doesn't even make sense, do bullets have rocket motors in them? No? Then they don't magically gain energy once they leave the barrel. This is basic physics.

The main thing missing is muzzle velocity vs barrel length and there is a separate ticket for that.

Fank added a subscriber: Fank.May 7 2016, 1:11 PM
Fank added a comment.May 16 2014, 9:16 PM

Issue closed as obsolete. If you encounter this problem again, please create another ticket. Thank you.