Bullet drop

[HagarTheHorrible]

When setting convergance does the program also allow for bullet drop or do they just cross the bullet streams at that point with no regard for gravity ?

 

 

Edited June 23, 2019 by HagarTheHorrible

[No.23_Gaylion]

Gravity is built in. Just fire long range while skimming the deck and you'll see your round hit low.... eventually. 

 

Also you have to think about the angle at which you are firing on. If you come in from a steep angle, gravity has less affect on the "drop" compared to firing from a level position. 

 

 Speaking of other WW1 flight sims, toying with that number does play with the impact of the rounds. 

 

 

[BMA_West]

1 hour ago, US103_Talbot said:

..

Also you have to think about the angle at which you are firing on. If you come in from a steep angle, gravity has less affect on the "drop" compared to firing from a level position. 

 

 Speaking of other WW1 flight sims, toying with that number does play with the impact of the rounds. 

 

 

 

So Talbot mind telling us where you put convergance on your SPAD and do you think this goes also for an SE5 or why not?

Edited June 23, 2019 by West

[No.23_Gaylion]

Minimum distance allowable. I put all convergence the same regardless of plane. I use same iron sights across all planes so that the sight picture in my mind never changes.

 

I dont know anything about an se5.

[HagarTheHorrible]

3 hours ago, US103_Talbot said:

Gravity is built in. Just fire long range while skimming the deck and you'll see your round hit low.... eventually. 

 

Also you have to think about the angle at which you are firing on. If you come in from a steep angle, gravity has less affect on the "drop" compared to firing from a level position. 

 

 Speaking of other WW1 flight sims, toying with that number does play with the impact of the rounds. 

 

 

 

 

Gravity might be built in but the question is, if I set my convergance to, for example 600 yds, does the game adjust the trajectory so that at 300 yds or so the bullet is 4 feet above my aim point (going by the above graph, more or less) so that by the time it arrives at the 600 yd point it is back to level with my sighting pip ?  I have to confess that the trajectory, going by the tracers, looks to be pretty flat, until gravity takes it's course, regardless of convergance (I'm experimenting with 1000 yds).  Given how close the weapon groups are in WW1 aircraft convergance is a bit of a  waste of consideration unless it also takes into account bullet drop between leaving the end of the barrel and reaching it's supposed destination ?  Going by the drawing above, if I set my convergance/sights to 1000 yds, it looks, extrapolating the trajectory back, as if the bullets should be climbing something like 10 feet above the direct point of aim, in order to arrive at the same level 1000 yds away ?

 

If my thinking is right, and it often isn't,  if I fire a steady stream of tracer, set to arrive at a point in space 1000 yds away, on the level (without being pedantic about bullet weight compared to non tracer) then that stream of bullets should, according to my limited understanding, arc up above the point I'm aiming at before arcing down to hit that point in space, lined up with my sight, 1000 yds away.  If it doesn't appear, to me, to do that in the game then what am I missing  (apart from everything ?) ?

 

Obviously the arcs in the diagram above are exagerated (fore shortened), the number are correct but the height and distance are different scales.

Edited June 23, 2019 by HagarTheHorrible

[No.23_Gaylion]

I agree that FC looks really flat but I am no game developer and can't question them on what's going on. I have plugged in the numbers they give into a ballistic program that maps trajectory and found the closer the convergence the better. But in the end, were talking a few feet or a few inches difference. 

 

How I figured my preferred settings and "confirmed" my ballistic findings was to repeatedly bounce AI aircraft again and again and again while switching the convergence around. 

 

There's a video on it but you'd have to join the 103rd to see it.

 

You can always jump in one of those free tanks and fire off the MG42 and see the rounds drop too.

 

Hagar, yes. It will actually cross the boreline twice. Once closer to the muzzle end and then back out where you have your sight ranged at, in your case 1000m.

 

In that other game it definitely changes when you play with your convergence settings. In this one, I'm not sure that it does yet and I haven't ran the same test like in that other game.

 

Also, even if you have your sight convergeance set close at say 65m, there is another point out there along the boreline that the rounds will cross as it drops back down. Which may or may not be 300m. 

 

Theoretically speaking...

 

Your mileage may vary.

Edited June 23, 2019 by US103_Talbot

[HagarTheHorrible]

TBH, I'm not really interested in bullet drop, as you say, over typical shooting distances, it makes little difference, I was just trying to think outside the box to see if it was possible to engineer the trajectory of the weapons on the SE5a to better match their correct true life angle of fire by setting absurd convergance ranges.  I wonder if the game "cheats" a bit and doesn't really apply a true balistic curve, more a laser line, until a certain point, way beyond useful engagement ranges, before applying a gravity effect.  It might well explain why distance shooting is maybe more effective in the game than real life accounts might suggest.

Edited June 23, 2019 by HagarTheHorrible

[No.23_Gaylion]

Cool.

[US103_Baer]

5 hours ago, HagarTheHorrible said:

  I wonder if the game "cheats" a bit and doesn't really apply a true balistic curve, more a laser line, until a certain point, way beyond useful engagement ranges, before applying a gravity effect.  It might well explain why distance shooting is maybe more effective in the game than real life accounts might suggest.

 

Or laser until the range set in convergence, then gravity?

 

Idk, in all my testing I couldn't find usable upward arc. 

 

Talbot's method is pretty good. Do tons of repeatable bounces, try different settings to find the one that works for you best. Then practise more with that.

 

[HagarTheHorrible]

I'm begining to wonder if range makes any difference in Box ?

 

If the only variable is the distance at which bullet streams converge, and dispertion effect,  and that the trajectory is otherwise very flat  out to long range.  I know it's possible to set the WW2 aircraft sights for range and target size, but if the bullets follow a straight line, rather than a curving trajectory, then all the sight settings are no more than flim flam and fancy dressing, you are essentially shooting in 2 plains rather than three ?

[Zooropa_Fly]

With 2 guns as close together as they usually are in ww1 crates, coupled with the fact (as I think mentioned above somewhere) that one shouldn't really be pulling the trigger until close enough not to miss anyway... I find the convergance setting of little practical importance.

In RoF's case, the wild bullet dispersion (particularly the Bristol or the SE5 if you watch zoomed in) makes for spray and pray shooting at distance anyway.

 

S!

 

[unreasonable]

1 hour ago, HagarTheHorrible said:

I'm begining to wonder if range makes any difference in Box ?

 

If the only variable is the distance at which bullet streams converge, and dispertion effect,  and that the trajectory is otherwise very flat  out to long range.  I know it's possible to set the WW2 aircraft sights for range and target size, but if the bullets follow a straight line, rather than a curving trajectory, then all the sight settings are no more than flim flam and fancy dressing, you are essentially shooting in 2 plains rather than three ?

 

Hagar, everytime the ballistics have actually been tested in the game, the results have been found to be reasonably accurate models of real trajectories. The is no "laser" path, please stop making things up. 

 

The best way to see this easily is firing from the runway, using the Aldis for FC crates, you can see the tracers are dropping from the centre of the ring immediately, accelerating earthwards. Zoom in: it is perfectly clear and obvious.

 

As for the vertical convergence: this is modeled in the WW2 planes, but I think not in the FC planes. If you fire a 109 F-4's guns on the runway, you can see that with a 1000m convergence the tracers start to climb well  above the centre of the sight ring before dropping back down - presumably at 1000m. Set at 100m, the tracers start right in the middle. Again this is clear and obvious. I do not see this with the Camel, either using the Aldis or iron sight ring, so it looks to me as though the guns are sighted flat and only the horizontal convergence is modeled, since as far as I can see the position of the sights is the same in each case.

 

Range makes a great deal of difference: at 1000 yds a 303 bullet fired by a Vickers will drop about 18.6 yards: but at 500 yds only about 2.4 yards!  That is still enough to make you miss if you do not adjust for it.

 

 

[No.23_Gaylion]

^This is what I figured as well.

[LukeFF]

17 hours ago, HagarTheHorrible said:

I'm begining to wonder if range makes any difference in Box ?

 

If the only variable is the distance at which bullet streams converge, and dispertion effect,  and that the trajectory is otherwise very flat  out to long range.  I know it's possible to set the WW2 aircraft sights for range and target size, but if the bullets follow a straight line, rather than a curving trajectory, then all the sight settings are no more than flim flam and fancy dressing, you are essentially shooting in 2 plains rather than three ?

 

You are way, way, way overthinking this. Yes, the bullets are affected by gravity and yes, the flight path they take is affected by convergence. 

[unreasonable]

1 hour ago, LukeFF said:

 

Yes, the bullets are affected by gravity and yes, the flight path they take is affected by convergence. 

 

Indeed, but specifically for the RoF planes now ported to FC, is the vertical flight path affected by convergence? From the gun-sight view I do not think it is, but I have not made a mission with a static camera to prove this one way or another. 

[LukeFF]

2 hours ago, unreasonable said:

Indeed, but specifically for the RoF planes now ported to FC, is the vertical flight path affected by convergence?

 

I haven't conducted any tests to see whether this is true.

[AndyJWest]

From a quick test, I can't see anything obviously wrong with the I-16 at 1000m convergence. The trajectory starts above the aiming line, and the rounds are converging. Whether they actually converge exactly at 1000m, and whether they are on the aiming line level at that point I can't say, with no means to judge the distance, and obviously the spread at that distance is going to be high (and correctly gets worse with a sustained burst). Why anyone would ever set convergence on an I-16 out that far, I have no idea.

 

If anyone has a serious point to argue here, rather than just engaging in pointless guesswork I suggest they provide some verifiable repeatable evidence. The burden of proof is on you.

[BraveSirRobin]

5 minutes ago, AndyJWest said:

If anyone has a serious point to argue here, rather than just engaging in pointless guesswork I suggest they provide some verifiable repeatable evidence. The burden of proof is on you.

 

This is crazy talk.  Do you want to shut this forum down?

[wombatBritishBulldogs]

https://youtu.be/_-soNrVIb8U

[LukeFF]

14 hours ago, Plank said:

And there is no designed bullet spread. They all home in on the convergence point.

 

This is why arguing with you has always been pointless. Yes, there is bullet spread and no, all bullets do NOT home in on one pinpoint location. It's been like that for quite a while now. 

 

 

[Guest deleted@83466]

15 hours ago, Plank said:

Well I had a bash in the I-16

 

This is what it looks like to me. and I am sure this is pertinent to the FC planes.

 

There is a line...... ...<SNIP>

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I don't know where to begin, but I'll just summarize by saying I think that almost none of the above is correct.  I'm guessing I've played a lot more IL-2 than you have, and I just think your observations are way off.  

Edited June 26, 2019 by SeaSerpent

[unreasonable]

12 minutes ago, Plank said:

 

The game as i understand observed it has a simple point of aim, it's on a line. If the bullets drop before

they get to that point then they will be below the level of the plane. 
 

 

Using Tacview to analyse ballistics in IL-2 is absurd: it does not even give aerodynamic data correctly.

 

Look at the two pictures below - taken from the game, on runway, no wind, using the Ishak. Top one is on convergence setting 100m, the other 1000m. You can see that the sight reticule is in the same place, and both vertical and horizontal convergence is modeled. (Unlike for the FC planes). This is the same for every single one of the WW2 aircraft.

 

 

 

 

[Guest deleted@83466]

How do explain this, Plank:

 

In DCS, about a month ago, with wingmen, we were flying Mi-8 helicopters armed with FAB-250 dropping bombs on a practice target.  My bombs straddled the target and one of them went dead-center and blew it up.   Confirmed by wingman observer.   Yet, when we brought up Tacview after the mission, it showed all four of my bombs going very wide of the target.  Another player did the same, and also noted Tacview showing the bombs not quite going where they were observed to have gone.  How do you explain that?

 

Tacview is great for evaluating ACM, but Unreasonable is almost certainly correct:  I wouldn't rely on it for precision analysis of projectile trajectories (maybe because the sampling time for data points isn't fine enough, don't know, and frankly don't care).  Look at Unreasonable's screenshots.  I find those a pretty convincing argument that you're wrong.

 

I'm not responding to you to convince you, but rather for the sake of others who might have an interest in this discussion.  I already know that nothing anyone says or points out to you will change your mind.

 

Edited June 27, 2019 by SeaSerpent

[HagarTheHorrible]

Does adjusting the convergence on the SE5a make any difference ?  I tried both extremes, 100m and 1000m but noticed no particular difference.  I appreciate the Vickers and Lewis arn't very far apart, maybe 3 ft,  but if I set 100 m convergence, should I not be able to see some divergence by the time the bullet stream reaches 800 m ( trace limit ?) ?

Edited June 27, 2019 by HagarTheHorrible

[AndyJWest]

One point to bear in mind when discussing dispersion is that, from what I remember the developers said that testing it on the runway could give misleading results as the aircraft vibration was greater than it would be in the air. From what I recall, this was in response to complaints that Bf 109s had worse dispersion than Soviet fighters, and was explained as being a consequence of the narrow-track undercarriage making movements more exaggerated. If you want to observe dispersion patterns properly, you should probably do it in flight, using the auto-level feature.

[No.23_Gaylion]

Good. Now check and see if the elevation can be adjusted in the ww1 planes.