Historical convergence for the p38?

[von_Michelstamm]

As I understand it, p38s weren’t harmonized due to the gun position, making them known for long distance shots.

whats the best setting in game for this?

 

1. Maxing our convergence at 1000 I think might tilt the guns up and make them arc more, rather than just using the natural ballistics of the rounds, so I don’t think that’s the solution.

 

2. This crappy image seems to suggest the rounds mostly crossed the point of aim at around 2000ft (609m). So Is 610m in game the most realistic choice?

 

 

[Pict]

Looks like an interesting chart...but it's at such a low resolution I can't read it, even when I click on the zoom feature..."2. This crappy image seems..." OK understood  

 

I have to say that with 300m convergence I have had no problem hitting targets with the P-38, and often blowing them apart. So now to try some tests at 610m convergence and see what that's like.

 

 

[jollyjack]

Rockets seem hard to hit a target with .....

[von_Michelstamm]

21 minutes ago, Pict said:

Looks like an interesting chart...but it's at such a low resolution I can't read it, even when I click on the zoom feature..."2. This crappy image seems..." OK understood  

 

I have to say that with 300m convergence I have had no problem hitting targets with the P-38, and often blowing them apart. So now to try some tests at 610m convergence and see what that's like.

 

 

I went to find the p47 chart to show you the scale and found one that has the lighting on it .

seems like 2000ft is the vertical convergence point.

its a dream in game, the sight ring behaves similar to a revi (no firing with plane behind the nose),

[Yogiflight]

How I understand it, the 'all guns' in the side view means, the middle of the guns, as some have a higher trajectory than the others. And the line for 'all guns' crosses the Sight line at 1500 feet. So this would be your convergence.

Edited October 10, 2019 by Yogiflight

[Swing]

Because of their location, clustered at the front, the convergence did not need to be set on the P38 ...The pilots seemed able to deliver group shots from 0 to 900 meters as well.

Edited October 10, 2019 by Swing

[von_Michelstamm]

5 hours ago, Swing said:

Because of their location, clustered at the front, the convergence did not need to be set on the P38 ...The pilots seemed able to deliver group shots from 0 to 900 meters as well.

 

That's IRL. In this game you can't turn off convergence. You also can't set separate vertical and horizontal convergence.
So, if you wanted to replicate the guns not crossing, you'd have to set the slider to 1000m, maximum. Problem is, the game then arcs your shots more than they would by their natural IRL trajectory, so that you hit point of aim at exactly 1000m.
I'm trying to get as close as possible to the correct historical vertical convergence, as that affects lead.

8 hours ago, Yogiflight said:

How I understand it, the 'all guns' in the side view means, the middle of the guns, as some have a higher trajectory than the others. And the line for 'all guns' crosses the Sight line at 1500 feet. So this would be your convergence.

 

Yes, you're correct, they're already dropping off past the sightline by 2000. Hard to tell, but it looks like 1500 or 1600. Thanks!

 

 

 

 

 

 

Edited October 10, 2019 by von_Michelstamm

[Yogiflight]

7 hours ago, Swing said:

Because of their location, clustered at the front, the convergence did not need to be set on the P38 ...The pilots seemed able to deliver group shots from 0 to 900 meters as well.

You don't need horizontal convergence, but you always need vertical convergence. No vertical convergence would mean, your gunsight and your weapons are directed straight on. As your weapons are below the sightline of your gunsight, it would mean your bullets will start parallel to the sightline, but under it and be all the time under your sightline, most likely never in your vision, as they drop due to gravity. The gunsight would be without any use.

Therefore you need to set a convergence, which means a point where your bullets drop from above the sightline to beneath it. Usually your weapons are under your sightline so the bullets first have to climb over the sightline, then fly for some time above it, to then, at the set convergence, drop under the sightline. There are two ways to do this, adjusting the weapons or adjusting the gunsight.

To make this clear, the Bf109 and 110 had both ways. For setting the convergence of the weapons there first was adjusted the gunsight so its sightline crossed the trajectory of the 20mm guns in 400m (later versions had higher convergence settings), because the 20mm guns were placed too far behind the openings in the fuselage, where the bullets left the plane. So you couldn't move the guns far enough up or down to adjust them to the correct convergence. After that the machineguns were adjusted to the gunsight, so their bullets crossed the sightline of the gunsight in 400m.

 

 

[Swing]

you are right Yogi, the vertical convergence still need to be adjusted ...but i don't know the value of that...and how apply that in game...

[AlphaHasen]

I found that. A bit blurred. ?

 

But you can see the maximum concentration at 600 feet ( ~ 180m ).

 

 

Edited October 11, 2019 by JG4_RuckZuck

[Sokol1]

Chart is from "Manual for Fighter Gun Harmonization" - 1945 (AAF 200-1)

 

http://www.avia-it.com/act/profili_daerei/libretti_velivolo/PA_libretti_PDF/Fighter_Gun_Harmonization.pdf

 

Better readable: http://libarch.nmu.org.ua/handle/GenofondUA/22938?show=full

 

https://ww2aircraft.net/forum/threads/aaf-manual-200-1-fighter-gun-harmonization.20658/

Edited October 11, 2019 by Sokol1

[von_Michelstamm]

15 hours ago, JG4_RuckZuck said:

I found that. A bit blurred. ?

 

But you can see the maximum concentration at 600 feet ( ~ 180m ).

 

 

So the correct number to dial in in game to replicate a real life plane, would be 180m?! Seems short.
Is that possibly just the base trajectory of the ammo without any vertical adjustment at all?

[AlphaHasen]

I would set the convergence to 200m-230m. You can use it up to 400m. 

 

You can see the upper cal.50 cross the line by 200 yard ( ~ 180 m ), lower cal.50 by 225 Yard ( 205 m ) and the 20mm by 250 yard ( 230 m ). 

Edited October 12, 2019 by JG4_RuckZuck

[Yogiflight]

@JG4_RuckZuck,sorry mate, but what you are referring to is not the convergence. The distances you name are the distances for the first crossing of the bullets with the sightline, where they climb over the sightline.

As I explained in my post above, this is not the convergence. The convergence is always where the bullets drop under the sightline, the second crossing, which is not on the drawing anymore, but somewhere around 550yards, as it looks. When your weapons are mounted above the sightline, like in one of the WW I birds or the German IFV SPz Madder, you don't even have this first crossing, where the bullets climb over the sightline.

[AlphaHasen]

Of course you are right. My mistake.

The second crossing of all weapons is at 1500 feet ( ~ 450-460 m ) . According to this document. 

This is really better. ? http://www.avia-it.com/act/profili_daerei/libretti_velivolo/PA_libretti_PDF/Fighter_Gun_Harmonization.pdf

 

Edited October 12, 2019 by JG4_RuckZuck

[[CPT]Crunch]

From a higher res version of the gunnery manual, readable.