Author Topic: Convergence Considerations  (Read 2553 times)

Offline RedBull1

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Re: Convergence Considerations
« Reply #30 on: November 16, 2012, 03:27:28 PM »
Average shots are 200-600.   :aok

Ok, I was just curious.  I find it fascinating that people really think that they can judge the difference in velocity and trajectory (outside convergence) to the point that that they drastically change their convergence.  Have you ever done the .target and seen the different between Hispanos and say Japanese or German 20mm?  Try it and you'll see how similar they are.  The German 30mm and the 37mm's are really the only black sheep in the family in terms of trajectory (using typical ranges under 600 yards).  Otherwise the .30 cals, .50 cals, and 20mm's are all very close, too close in my opinion to make the minute calculation changes in a knife fight (200-400 yards). To each his own.
When I am leading a shot I notice a massive difference between Ki84/German 20's and hispanos
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Offline RTHolmes

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Re: Convergence Considerations
« Reply #31 on: November 16, 2012, 05:42:29 PM »
thats what I was thinking, unloaded and level they may all seem similar but when you're pulling lead at 5G theres a much bigger difference between them - the higher KE rounds dont drop away anywhere near as quick.
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Offline SmokinLoon

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Re: Convergence Considerations
« Reply #32 on: November 17, 2012, 06:57:42 PM »
Be sure and remember that a 20mm warhead's velocity and weight (kinetic energy ), is different from it's ability to do damage.  The projectile is not effected by velocity unlike FMJ's of the .30 and .50 cal MG's.

Here is a link to a website that does a great job at explaining the different 20mm rounds of WWII.

  http://www.quarry.nildram.co.uk/an_introduction_to_collecting_20.htm
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Offline save

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Re: Convergence Considerations
« Reply #33 on: November 18, 2012, 01:19:33 PM »
400 across the board.



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Offline bustr

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Re: Convergence Considerations
« Reply #34 on: November 18, 2012, 03:40:26 PM »
Aces High General Types of Guns

MG
Type97.7.7mm..750m/s...Bullet=13.2g
Brit.303............762m/s...Bullet=11.3g
MG17 7.92........865m/s...Bullet=11.5g
MG131.13mm....750m/s...Bullet=76g
AN/M2.50.........850m/s...Bullet=112g
UB-12.7...........850m/s...Bullet=64g
Type3 13.2.......789m/s...Bullet=52g

20mm
Type 99-1.....600m/s...Bullet=200g
MG151/20.....720m/s...Bullet=205g
Ho-1 20mm...750m/s...Bullet=164g
Ho-5 20mm...750m/s...Bullet=84g
ShVAK 20mm.770m/s...Bullet=96g
Type 99-2.....750m/s...Bullet=222g
Hs404 20mm.880m/s...Bullet=257g

30-37mm
Mk108 30mm.500m/s...Bullet=336g M-Gesch
M4-37mm......610m/s...Bullet=608g HE
Mk103 30mm.860m/s...Bullet=336g M-Gesch
NS-37 37mm.880m/s...Bullet=760g AP
NS-37 37mm.900m/s...Bullet=735g HE

Time to Target in seconds.

---Target---100---200---300---400---500---600--yards
Bullet Speed
---500m/s---.20---.40---.60---.80---1.0---1.2--seconds
---600m/s---.16---.36---.54---.72---.91---1.0
---720m/s---.15---.31---.45---.61---.76---.91
---750m/s---.14---.29---.44---.59---.72---.87
---762m/s---
---850m/s---.13---.26---.39---.52---.65---.77
---865m/s---
---880m/s---.12---.25---.38---.51---.64---.76

Combat Speeds 90 degree left<--->right Travel in Yards.

--Time----.10--.20--.30--.40--.50--.60---.70--.80--.90---1.0--1.5--seconds
Speed
250mph---11---22---33---45---56---67---78---89--100--112--168--yards
300mph---14---29---43---58---73---87--102--116--131--146--219
350mph---17---34---51---68---85--102--119--136--153--171--256
400mph---19---39---58---78---97--117--136--156--175--195--292

Speed mph to yd/sec

250mph = 112 yd/sec
300mph = 146 yd/sec
350mph = 171 yd/sec
400mph = 195 yd/sec
450mph = 220 yd/sec

Fighter Wingspans

P51D ---12.3 yards
109 -----11.0 yards
Spit ---- 12.0 yards
P47 ---- 13.6 yards
Fw190 - 11.5 yards
P38 ---- 17.3 yards
A6m5-- 13.0 yards
P40E --- 12.3 yards

Gunsight Rings at Range

50mil at 100yds = 4.0yds
50mil at 200yds = 9.7 yds
50mil at 400yds = 20 yds
50mil at 600yds = 30 yds

60mil at 100yds = 6.5yds
60mil at 200yds = 13 yds
60mil at 400yds = 26 yds
60mil at 600yds = 36 yds

100mil at 100yds = 8.3yds
100mil at 200yds = 19 yds
100mil at 400yds = 40 yds
100mil at 600yds = 60 yds

120mil at 100yds = 13yds
120mil at 200yds = 26yds
120mil at 400yds = 52yds
120mil at 600yds = 66yds
bustr - POTW 1st Wing


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Offline bustr

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Re: Convergence Considerations
« Reply #35 on: November 18, 2012, 04:23:52 PM »
If you fly auto level at Max Cruise from the E6B and pull up the offline target, your fighter's centerline will be alined level with the center of the target. Test your convergence patterns at 200, 300 and 400 if you are looking for pattern densities for air to air against fighters. Pull convergence out past 400 for bombers and ground straffing.

.target range(1-36,000) heading(0-359) azmuth (0-359)

Flying east at Max Cruise to test 300 yards (.target 300 90)

North=0, East=90, South=180, West=180

Each ring on the Offline Target is 10ft wide.

Because of different (initV) between dissimilare rounds like the german MG versus Cannons, you see armerors diagrams showing MG set to 400m and cannon to 550m. This gave a combined trajectory sweet spot 40cm above the gunsight centerline at about 250-300m for close fighter combat with a known 550m convergence spot with the gunsight level line for shooting bombers when the cannon rounds dropped back down through the sight line. Testing combinations of convergence harmonizations at 200, 300, 400 to see how they density pattern on full zoom will give you an idea of what to expect within reason in the game.

The closer into the wingroot your wing guns are like the FW's, your shooting style technique will be more like shooting with a 109 or yak. Choosing your convergence combinations at that point is an attempt to verticaly tighten your pattern between 300-450 since horizontaly your wingroot cannon are only a bit wider spread than your hood MG.

A unique hybrid of this is the C.205. Test it offline against the target with the MG at 325 and Cannon at 400.  200, 300, 400 autolevel and first shoot MG then shoot cannon and watch the patterns.

In this game wing only guns need to have a tight patterning whatever convergence range you choose. I've experimented setting multiple guns 50, 75, 100 yards apart in convergence. 25 yard differences seem to not allow cons to fly between the rounds in the game. Wing gun convergence suffers most from not setting your tightest density to the range at which you fight. Most of us shoot at each other between 250-350.



 
bustr - POTW 1st Wing


This is like the old joke that voters are harsher to their beer brewer if he has an outage, than their politicians after raising their taxes. Death and taxes are certain but, fun and sex is only now.

Offline Babalonian

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Re: Convergence Considerations
« Reply #36 on: November 19, 2012, 12:50:22 PM »
titanic3 300 is not displayed as a range for an enemy target during flight (800,600,400...).  So at what range do you start to shoot?

Thanks.

You trust/depend on the displayed icon range?   :confused:  I use the gunsight, bustr has written up about it a few times on these forums in detail the methodoligy of it, but you train yourself and then through practice and use become a lot more proficient (and accurate) at guaging your targets distance via its displayed ratio through your gunsight recticle. 

Oops, nm.
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Offline Iraqvet

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Re: Convergence Considerations
« Reply #37 on: November 20, 2012, 07:18:31 AM »
400 or less for me, up close and personal  :lol
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