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Offline Danoffski

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Changing bullet speed?
« on: 13 Nov 2008, 17:34:21 »
This is a request for realism,

the bullet speeds are extremely slow in small arms, the delay from when you fire a small arm and the bullets arrival time is so slow or out of proportion in ArmA or OpFLash that you must aim in front of a running person, when in reality even when watching someone shot at a pond of water using a spotting scope because the distance is too far for the eye to see you can still not even detect this delay shooting with a 222 rifle I have done this experiment personally you cant even notice a delay by eye with a spotting scope when the bullet hits the water after fire, remember a bullet is much faster than the speed of sound! I hope this gives you an idea of how fast a bullet is in the real world. You cant out run a bullet like in Operation Flashpoint point or duck before it hits your location if your far away. This takes a major portion of realism down the toilet for the whole game and it's a pity that I really want to see fixed! Why not at least put the option or fix in Vet mode?

Changing bullet speed how ?
So my question to the all knowing ArmA guru is how can I stop all bullet delay in game?? (For Small arms only, as cannon dose have a delay) Is to be found in the "config.bin" perhaps, no idea?  :banghead:

Offline laggy

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Re: Changing bullet speed?
« Reply #1 on: 13 Nov 2008, 20:40:00 »
Hi there,

I believe BIS forum is a better place for this discussion, since it has to do with game engine stuff.
However, I have fired many different firearms, ranging from pistols and huntingrifles to machineguns and I find the bullet speeds in OFP and ARMA to be very realistic.
If you fire a 9mm pistol at a target 50 metres away you definetely hear a delay between shot fired and impact.
I guess bullets travel faster wherever you are from.

Laggy
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Offline Wolfrug

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Re: Changing bullet speed?
« Reply #2 on: 13 Nov 2008, 21:52:51 »
There are ways to do this of course, for instance capturing the bullet using a "fired" eventhandler and giving it a little boost using setvelocity. The other option would be to change the muzzlevelocity in the, I think, cfgmagazines config which determines at what speed the bullet leaves the weapon.

But otherwise, I believe bullet speed and bullet trajectories in ArmA and OFP are in fact very properly modelled. You can try it yourself in for instance this little widget: Kronzky's Moveable Target Range. Just shoot different guns and watch the trajectories differ, then compare them to real-world data, and you should find that they're really not that far off :)

Finally, also remember that the human brain is not as fast as you'd want it to be. The time it takes to aim, order the brain to pull the trigger, and for the trigger to be pulled and the bullet to be shot is plenty of time for a target hundreds of meters way to move out of the path of the bullet. Shooting ahead of the target is the only way to hit, quite simply, if the target is not running straight at you :P

Other games don't simulate bullets at all, they basically just create death zones in the middle of your screen the same instant you fire - which is fine in short ranges, but no good when fighting a real war, eh?

Wolfrug out.
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Offline bedges

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Re: Changing bullet speed?
« Reply #3 on: 13 Nov 2008, 21:59:33 »
And to insert a wee bit of Devil's Advocacy here:

it is only a game after all  :whistle:

Offline Danoffski

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Re: Changing bullet speed?
« Reply #4 on: 14 Nov 2008, 02:04:45 »


Because of the ignorant statements in this room I'm going to have to have to leave some of you wallowing in the pools of your own embracement just remember I'm not trying to make fools of you because by your own statements you have done so yourselves. Listen and let me tell you all something so you might learn something, the link below shows calculated bullet speed normally 1200 m/s a person who is being shot at in ArmA or flash point who is 50 m away and running (a fair distance)

Can move how far when a bullet is travelling 1200 M @ Second  or more?

So disengage you big mouth and engage your big brain and tell me how far that person can run in that faction of a second it takes the bullet to traverse 50m ? If the gun goes off when he is in the sight the bullet will be there with no noticeable delay. Before you want to argue I suggest you get your facts straight and actually know what your talking about.
Thank you very much
 :good:

http://64.233.183.104/search?q=cache:pjJ8tmkelFoJ:hypertextbook.com/facts/1999/MariaPereyra.shtml+bullet+speeds&hl=en&ct=clnk&cd=1&gl=uk

Offline savedbygrace

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Re: Changing bullet speed?
« Reply #5 on: 14 Nov 2008, 03:37:36 »
Whoah, lets reign in the horses here a bit partner, these fellahs are merely expressing opinions in an attempt to be helpful.
First of all, welcome to the forums.

Lets revisit their comments shall we?
Quote
I have fired and I find
This member made a comment based on "HIS" experience
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you definetely hear a delay between
This member made a comment based on "HIS" hearing
Quote
But otherwise, I believe bullet speed and bullet trajectories in ArmA and OFP
This member made a comment based on his belief
Quote
Finally, also remember that the human brain is not as fast as you'd want it to be. The time it takes to aim, order the brain to pull the trigger, and for the trigger to be pulled and the bullet to be shot is plenty of time for a target hundreds of meters way to move out of the path of the bullet.
This member made a comment referring to the brains thought process which effects everyones reaction that precedes the actual ballistics science that occurs when the hammer needle penetrates the powder cap of the casing head and ignites the powder within which in turn forces the projectile from the casings embrace. 

Ballistics is a fascinating study of science and would take much more than scanning a project datasheet submitted to a website by a class of highschool students to examine it's "full worth. BUT this is a game as this admin stated
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it is only a game after all

And no one here is truly in any position to debate the physics of Internal and External ballistics and I am sure they did not intend to.

Besides, If you take a moment to reflect on the actual logic...you will find that even with a target sighted, the internal ballistics still does not occur until the weapon operator "begins the thought process which initiates the physical action to engage the hammer". So, In that fraction of a second, a target in motion has plenty of time to effect the accuracy of the shot(not the actual ballistic science). And just to highlight...a pond is normally not a moving target.

Please consider that these members were attempting to be helpful and try and reframe from bashing them with harsh comments. Thank you for your cooperation friend.
« Last Edit: 14 Nov 2008, 03:41:25 by savedbygrace »

Offline loki72

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Re: Changing bullet speed?
« Reply #6 on: 14 Nov 2008, 07:17:49 »
Quote
Because of the ignorant statements in this room

Quote
wallowing in the pools of your own embracement

Quote
So disengage you big mouth and engage your big brain

 ???

not sure what forum you think you're on friend...

but as a friendly reminder...

we don't treat other members that way here.

Quote
Listen and let me tell you all something so you might learn something

i'd listen to this advice... after all it is yours.

 :)


edit:

to put something useful in this subject.

first of all... you will never get real world ballistics on 'your' pc...

even if running an uber machine as i am.. 60+ fps continous... the game engine limits and the animation speed / complexity will determine the 'overall' speed of which you speak. you can change the bulletspeed = xxx in the config.cpp all you want.. but it won't give you the 'realisim' you seem to be after. (you'll just miss them faster)

and none of this takes into account if you are playing MP.. which increase the 'misses'.... it is a game after all.

 :good:
« Last Edit: 14 Nov 2008, 07:46:38 by loki72 »

Offline Sparticus76

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Re: Changing bullet speed?
« Reply #7 on: 15 Nov 2008, 03:00:12 »
Just a little bit of background. I'm currently in the Australian army, crew commander of an armoured vehicle, have served for 8 years now.
 If you're after realism, then you have to aim off. We have a range shoot where you engage moving targets at running speed and walking speed and even at 100m, using an F88 Styre, 5.56mm...you have to aim off. This is from the site you had in your post..

.22 rimfire cartridge 1200-1500 fps
.22 centerfire cartridge 2400-3000 fps
.22 Swift 4000 fps
.38 Special 600 fps
.221 Fireball 2650 fps

The .22 is 1200 - 1500 fps, not 1200 m/s, one foot is alot shorter than one meter.
The cannon on my armoured vehicle fires an armoured piercing round at 1300 m/s, small arms mostly fire below the 1000m/s mark, around the 850 m/s area.
Hope this helps out, realism does help keep interest in this kind of game.
« Last Edit: 15 Nov 2008, 11:02:36 by bedges »

Offline Mr.Peanut

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Re: Changing bullet speed?
« Reply #8 on: 19 Nov 2008, 16:15:42 »
scratch identical comment already made
urp!

Offline Ext3rmin4tor

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Re: Changing bullet speed?
« Reply #9 on: 26 Nov 2008, 14:48:17 »
Besides I wanted to add that the bullet speed you find in weapon specs is the starting speed. You must consider that the air friction will slow it down alot since it's an exponential function and it depends on the object mass and shape. A bullet doesn't have a great mass so it will be slowed down a lot. I don't know if sparticus can clarify this more than I did since I think a tank commander has a far better knowledge about this stuff than me.
How can you shoot women and children?
Easy! Ya' just don't lead'em so much! Ain't war hell?!!

Offline Tyger

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Re: Changing bullet speed?
« Reply #10 on: 02 Dec 2008, 20:22:36 »
I am an 11A in the US Army, and have deployed to OIF VI. The weapons used in game are the same weapons I deployed to the Sandbox with. They fire a 55 grain or a 62 grain projectile, depending on the ammunition used, at approximately 2700 feet per second, depending on the exact charge of the round. My M4A1 fires on average at 2732 feet per second.

Target is at 2700 feet. Flight time is therefore 1 second. Target is moving across your front at 3 mph - an average walking pace. 3 mph is 4.4 fps doing the conversion. In the time that it takes the bullet to travel that distance, the target is 4.4 feet away from the intended point of impact. 2700 feet is 822.96m. Let's assume that the standard engagement range is about 200m. This is appx. 1/4 of the distance. Therefore, our target will have moved only 1/4 of the distance left, or 1.1 feet. In order to effectively engage a target at 200m, you will need to lead your target by 1.1 feet. In layman's terms, you will need to aim your weapon 1.1 feet in front of the target. This adjusts the point of impact to the position the target will be at in the span of time it takes for the bullet to travel 200m.

Next, factor in human reaction time. Mean reaction time is 180 - 200 milliseconds [1]. This means that in the time it takes for your brain to send the "Squeeze the trigger/Click the mouse button" command until the finger receives the command, your target has already walked .22 feet. This means that in order for your point of impact to be on target, you will now need to aim 1.32 feet in front of the target.

That being said, if you feel that the bullet speed is too slow for you, feel free to create a script which "catches" every bullet fired, analyses their velocity, and then increases the velocity in the appropriate amounts. Just bear in mind that this will greatly increase the amount of CPU used, as well as require a fair amount of trigonometry knowledge to script something of the sort.

 
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Offline loki72

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Re: Changing bullet speed?
« Reply #11 on: 02 Dec 2008, 20:40:05 »
WOW

 :clap: :good:

that's the kind of information that goes a long way.. no pun intended...

Offline Tyger

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Re: Changing bullet speed?
« Reply #12 on: 02 Dec 2008, 21:14:08 »
@ Ext3rmin4tor

Also, just for general information, air resistance on a projectile is negligible. Of course, in RL it will play some slight, minuscule effect on the velocity of the bullet, but bullets are shaped in order to decrease this effect (minus wad cutters, if you are familiar with them). Now, that being said, a bullet in flight can easily be susceptible to wind, because the side profile of the round is not shaped to decrease wind resistance on it. Therefore, on a windy day, the accuracy of your shots will be skewed because the round is pushed by the wind.

What affects your accuracy the most is gravity. If anyone cares to have them, I can scan the charts I have for zeroing. But the short of the long is, when zeroed with iron sights by US Army standards (a 25/300 meter zero), due to the arched shape of a projectile's flight, if you were to aim center of mass at a target 500m away with an M4, your point of impact would be about 65 inches below the target. If you were to sight your irons by USMC standards of 36/300 yards, the point of impact when aiming at center of mass at 500 yards would be 49 inches below target.
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Offline Sparticus76

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Re: Changing bullet speed?
« Reply #13 on: 03 Dec 2008, 08:10:51 »
Human reaction time of course would only be a factor if "ambushing" targets....ie, you know that at 200m, you need to aim off 1.1 feet, so you keep you aim steady in front of a target walking right to left and attempt to shoot when he reaches 1.1 feet from the crosshair. However it's better to shoot at a moving target while leading it, that is move your crosshair with the target, 1.1 feet in front of it and release the shot, therefore human reaction time will not come into it.

Offline Tyger

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Re: Changing bullet speed?
« Reply #14 on: 03 Dec 2008, 14:19:37 »
Human reaction time still applies - there is still a delay between the time that you decide to fire and the point that the weapon actually fires. This is because you think, I'm leading the target effectively. I need to squeeze the trigger now. Then, your brain sends the signal, which is just ever so slightly delayed from the actual point in time that you though Fire!.

You did make a good point about tracking a target. By tracking the target, you have a higher probability of success. This is, again, due to the fact that there is that slight delay in between your brain's command and your finger's reception of the signal. Call it Reception Time if you will...
« Last Edit: 03 Dec 2008, 14:24:48 by Tyger »
"People sleep soundly at night only because rough men stand ready to do violence on their behalf." - George Orwell

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