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NonWonderDog

Realistic Ballistics

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Oops, I completely forgot to include them in the new version. I've uploaded v1.53 that includes the in-game range cards again. Sorry about that.

The online error message should be fixed, as well, and I've changed the M1A1 loadout to 27 APFSDS-T and 13 HEAT-T because that's the standard combat load. HEAT muzzle velocity is slightly tweaked, but I haven't done the ballistics for tank shells other than that.

Thanks so much.

Your add ons are amazing. Before I installed these add ons I couldn't really play because I always miss, I think the dispersion was too much, I don't know.

Now I can do really well and have a blast with the ballistics, sight adjustments, range finder, and scope fix.

I only wish you could always have the range finder equipped. smile_o.gif

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I only wish you could always have the range finder equipped. smile_o.gif

i second that...although finding range via dots and arranging elevation is realistic it would help to have a digital range finder on the binos so u can straight adjust ur elevation...

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OpticsZoom is not a multiplier of 120 degrees, though. It's the half-field in radians. Field of view in degrees is thus approximately opticsZoom * 114.6 degrees. I've confirmed this with a big box marked in meters and custom optics models, with everything uv-mapped by hand. It's in radians.

I didn't really define opticsZoom = 0.30 as unity power, either, that's a simplification. I defined 4x power reticles as 7 pixels per mil on a 1024x1024 image since it was the nearest whole number that fit (mostly) the whole field of an ACOG scope on the screen. I could have done 8 px/mil to make unity power equal to opticsZoom = 0.256, but the ACOG field have been clipped off pretty severely (this was the first optic I did, remember). I scaled all the other magnifications to the nearest whole number based on that, and then worked backwards to find the opticsZoom values. Unity power varies between 0.28 and 0.3 radians half-FOV for all the optics.

I did it this way because field of view and reticle dimensions are much more important than perceived magnification. You can't tell that something is strictly 4.25x instead of 4x, but if the BDC reticle and rangefinder are completely off, you will notice eventually.

If you want to know exactly what unity power "should" be, use this formula:<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">opticsZoom = atan( (horizontal screen size)/(2*distance from monitor) )

This assumes a 4:3 monitor, and you'll have to adjust the horizontal size if you have something else. For a decent sized monitor (anything bigger than a 17" CRT), this will be anywhere between 0.25 and 0.30. I chose the high end of that range, so I could fit more of the wide-FOV optics on the screen.

...

Well seems logical to me, probably a lot better than my totally theorical explanation (even if results are not so differents).

...

I found some firing tables for Swedish ammo out of the 120mm Rheinmetall L44 (in Swedish...) on the Steel Beasts website, so that's a help. I don't know how this compares to US ammo, but "120/95 slpprj 95" seems to be comparable to M829A2 according to info here.

None of the rounds listed seem to have any relation to M830, though.

And, just now, I found all the data I need for the US 120mm shells. I get the distinct impression that whoever unclassified this wasn't doing their job, but hey. Works for me.

Well what do you need? Rangecard with real life gun elevation, flight time for a few distances, shell speed for different distances?

I have done some research on the net about tanks optics magnifications and fov but it's quite hard to find both fov and magnification.

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Hey NWD would it be possible to add a mildot calculator that you can bring up like the compass or something and just put in the mil dot height and it automatically does the (height*1000)/mil=range.

Perhaps combined somehow with the range cards if necessary?

One could also add common heights for objects in meters to use with the formula on a range card.

I know, I could grab a calculator and do it myself, but it'd be much easier to just have it in game.

notworthy.gifnotworthy.gifnotworthy.gif

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Oops, I completely forgot to include them in the new version. I've uploaded v1.53 that includes the in-game range cards again. Sorry about that.

The online error message should be fixed, as well, and I've changed the M1A1 loadout to 27 APFSDS-T and 13 HEAT-T because that's the standard combat load. HEAT muzzle velocity is slightly tweaked, but I haven't done the ballistics for tank shells other than that.

the 1.53 download seems to be missing the NWD_ExtraBallistics.pbo which came with the 1.52 download...

was this intentional? Dunno if I should remove that file or not...

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Glad to see someone on these forums has discovered filefront, and thanks for all the hard work.

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I have version 1.00 installed! If I want to install the latest version then what should I do with NWD_RealACOG.pbo ??

Do I still need that one or must I delete NWD_RealACOG.pbo ??

Not much info in the RAR-file is there?

Thanks in advance.

Best regards, Claymore.

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Hy Claymore,

I always removed the old folder completly and replaced it with the new version. Worked always well.

Think something like that is posted on the first post of this thread.

Cya

BTW

GREAT JOB NWD.

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With this mod enabled, I seem to be having a lot of difficulty hitting laser designated targets with the harrier. I suspect that the maneuverability of the bombs may have been affected by some of your changes. I would like to let you know, though, that aswell as your mods I had trueview and fdf sounds running... then when I tried it with no mods, the bombs were more accurate. It could be that another mod is affecting it, but I thought I would start here first! I've only tried with all and no mods, and only online.

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The bombs, by default, were more maneuverable than AIM-9x missiles.

So yes, you'd be correct if you've noticed less maneuverability from your laser-guided bombs. In real life you're still supposed to use CCRP or CCIP mode to deliver laser-guided ordinance. The guidance is used to improve the accuracy, not make it magically hit wherever you want from any delivery angle.

I gave the bombs a larger blast radius to compensate, since they had a smaller blast radius than artillery shells before. crazy_o.gif

I probably still have to tweak this, though. You're forced to fly too low for the bomb to fall on target without an accurate solution, and there's no way to get an accurate solution. If there was a CCRP computer with a loft profile built in, low bomb maneuverability wouldn't be a problem.

On top of that, the game doesn't seem to handle low maneuverability values very well at all. There's a good chance your bombs are only a few inches off-target, but they're blowing up prematurely and doing no damage. This happens with the Javelin within 400 m range, for instance.

This is part of the "NWD_RocketBallistics.pbo", if you want to get rid of it.

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The bombs, by default, were more maneuverable than AIM-9x missiles.

So yes, you'd be correct if you've noticed less maneuverability from your laser-guided bombs. In real life you're still supposed to use CCRP or CCIP mode to deliver laser-guided ordinance. The guidance is used to improve the accuracy, not make it magically hit wherever you want from any delivery angle.

I gave the bombs a larger blast radius to compensate, since they had a smaller blast radius than artillery shells before. crazy_o.gif

I probably still have to tweak this, though. The game doesn't seem to handle low maneuverability values very well at all. There's a good chance your bombs are only a few inches off-target, but they're blowing up prematurely and doing no damage. I've started to notice this with a few different weapons I've tweaked.

On top of that, you're forced to fly too low for the bomb to fall on target without an accurate solution, and there's no way to get an accurate solution. If there was a CCRP computer with a loft profile built in, low bomb maneuverability wouldn't be a problem.

This is part of the "NWD_RocketBallistics.pbo", if you want to get rid of it.

It was far from a magical thing..

During our testing, without your mod we could get a bomb to hit within 10 meters of the laser target when dropped from a distance of 2 kilometers at 1000m at 600 km/h. With your mod, the bomb will miss by hundreds of meters sometimes, and the only way to reliably hit near the target was to treat it is if it had no guidence at all.

The gbu-12 has a range of up to 8 nautical miles in real life and, according to wikipedia (because I was too lazy to find a primary source)

Quote[/b] ]

According to Raytheon's face sheet for the PAVEWAY 2, 99 deliveries of guided munitions will yield a circular error probable(CEP) of only 3.6 feet, vice a CEP of 310 feet for 99 unguided bombs dropped under similar conditions.

Have you been able to get better accuracy with the gbu-12s out of your mod? Currently, the laser target lock will expire before you get anywhere near a parabolic path for the bomb. It seems that the laser target locks expire for me within about 1800m-2500m to target, given a completely unobstructed view. With the less maneuverable bombs, it's not possible to sustain them in the air long enough, and your window to ensure a successful hit is very narrow.

edit: Completely coincidentally, the CEP of these guided bombs and me dropping them without a hard lock matches almost exactly the alleged CEP of the unguided bombs that ratheon found. There's nothing to this, I don't think, but it just dawned on me that the numbers were very close. I had a friend on the ground that was doing some loosey-goosey estimates with the binoculars, etc.

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I'll look into it. I hadn't noticed accuracy that bad, but I do expect the occasional miss if bombing at low level and high speeds. You really do need to use a computer calculated release point to get that 3.6 foot accuracy.

It seems that the indirect hit range is bigger than I expected it to be, too. I'll back this off to where it was or slightly higher. Undocumented values with illogical behavior are annoying.

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One more thing:

If the in-game range cards aren't enough for you, here's a more detailed set of cheat sheets:

qvcaeyjnag.jpg

Hi All,

Since the last update 1.53, I've found that using the range card provided the sight adjustment are not as accurate as before for example using the target range, for M107 at 1000 m the sight should be adjusted to 19.25 and I found it more accurate at 20.25.

Somebody else could see if it's me or a balistic problem ?

Thanks.

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Hi all

Here's a question I have wondered for some time.....Can and will teh velocity and ballistics on the RPG and AT Rocket projectiles be fixed to realistic? I think a bottle rocket flys faster than them.

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A little thought, Flasher. Have you checked to see if the M107's scope is in MILs, rather than the MOA it should be in?

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I've read your post that I replied to in detail, so what I said was wrong biggrin_o.gif.

Erm, I have noticed something a tiny bit off, but i've not been fussed by it. It's out by 1 MOA as you say, but I have put that down to something I was doing.

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If I understand this right.

a) When

NWD_Ballistics v1.53

- @NWD_Ballistics

  - Addons

     - files

is installed on the server and activated with the -mod= param, then no client need to use the same addon? It's optional or for your own singel mission?

b) If used by client only, the addon will not affect the ballistics for other players, and it will not affect you either because then the vanlilla server will override your config?

c) @GMJ_SightAdjustment and @NWD_ScopeFix do not have any meaning on the server, other than maybe verify the clients files (Anti Cheat Purpose)?

Or has I understood this all wrong?

Anyway awesome just awesome.

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Online, the mod will affect the projectiles of the clients who have it enabled only.

So if installed on the server it will only affect AI on server?

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Online, the mod will affect the projectiles of the clients who have it enabled only.

So if installed on the server it will only affect AI on server?

Yep, looks like it smile_o.gif But you may force the clients to use the mod with equalmod thingy.

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Thx for the reply

My q: A and B is answered

One more to go:

c) @GMJ_SightAdjustment and @NWD_ScopeFix do not have any meaning on the server, other than maybe verify the clients files (Anti Cheat Purpose)?

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Hi all

Here's a question I have wondered for some time.....Can and will teh velocity and ballistics on the RPG and AT Rocket projectiles be fixed to realistic? I think a bottle rocket flys faster than them.

What do you mean? I've changed them in the "rocketballistics" pbo; are you saying they're still too slow?

The RPG launch speed is exactly correct (115 m/s instead of the ridiculous 5 m/s in the default). Even the 0.1 second stage delay is accurate. I don't remember how believable my thrust data was, but I gave the rocket 280 m/s/s acceleration for 1 second. In any case, the RPG reaches its correct maximum range of ~900 m after the correct 4-4.5 seconds. (The trajectory is completely wrong, though, since it seems to have active control surfaces and/or vectored thrust keeping it level as long as the motor is running. I could probably give it zero thrust in the config and script the trajectory instead, but that would take time and effort. I know exactly what the trajectory should look like from the BDC reticle, so it's just a question of moving thrust into a script.)

The tandem warhead round is ~30% slower all around. I don't know if it's supposed to be, but it would be if it used the same boost charge and sustain motor. It probably does use the same rocketry, but I have nothing backing that up but gut feeling and a couple half-remembered sources saying the tandem warhead had "40% less range".

The AT-4 shell might have too much drag on it, but I have no way of verifying it one way or another. It's the same amount of drag as on the RPG rounds, so it shouldn't be too far off. The launch speed, however, is exactly correct (285 m/s), so it shouldn't be a problem at ranges below 300 meters. At ranges above 300 meters, you shouldn't be taking the shot anyway.

The M136 AT-4 projectile has no rocket motor, of course, as it is not a rocket. It's an 84mm recoilless rifle shell, and it behaves as such in my mod.

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