Author Topic: a simple rule for gunnery range?  (Read 1646 times)

Offline bustr

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Re: a simple rule for gunnery range?
« Reply #15 on: March 15, 2012, 06:11:03 PM »
This is why all of you have to aim on average 10Mil high while flying level 6 and shooting past 200 to about 600.

Drop Compensation

When you pick your convergence in game your gunsight center is zeroed to that distance.

In real life your armourer would average the center of the gunsight against your harmonization patterning of vertical impact and horizontal convergence so your drop was compensated for 200-400 with wing mounted guns. The N9 gunsight in the P51 had a Hi/Low mounting for straffing and air to air along with whatever your armeror could accomplish if he went outside of regs.

In WW2 pilots were able to place the pipper on the target 200-400 becasue of this adjustment. In Aces High unless you build your gunsight with a drop compensation shadow line or other markings, you have to remember to include the loft calculation along with your lead calculation during your "Kentucky Windage" personal moment.

Hitech is very kind to us with motor mounted cannon by not locking them level with the airscrew shaft. You get to tilt them UP to zero their IP at your chosen convergence range in the hanger to verticaly harmonize with the hood MG. Other wise in real life the round had no loft leaving the prop HUB but, instead archs downward. Even at game convergence 150 the rounds go up slightly at first then arch down. If he locked the HUB cannon like real life, with 20mm and Ns-37 it just means you shoot low by about 8-12 inches out to 400. MK108/30 by 12 feet low. Bf109's with HUB mounted MK108 had their Revi gunsight centered to (-366cm) at 400M. The Ta152 was probably set this way also.

Our gun barrels are right hand spiral. So your rounds are affected to some degree by right hand "spin drift". At most maybe 6-12 inches at 1000 yards on avereage for .30, .50 and 20mm munition in our fighters. I've been reassesing some documents for the MK108/30mm and I beleive it has an 18 inch right hand spin drift at 400 meters with an average 12 foot(3.68m) drop. 27inches(68.376cm) right hand drift at 550M with an average 24 foot(7.68m) drop. I finally ran a modern spin drift calculator against the MK108 (physical structure),Mass,Msec,RoT and it showed the german values to be in centemeters. At least I've kept beating my head against my own bias over the past few years.

Blasted german ballistics techs in WW2 use .xxx for mm, xx.xxx for cm and xxx.xxx for M. Not mm, cm, M. But they use mm, cm, M in aircraft ariframe, engine and armerours manuals. I've been using xxx.xxx to interprit a spin drift chart for the MK108 for some years now becasue the values are input to the chart as xx.xxx while the ballistic drop values in meters were entered as xx.xxx by the same techs. Buttt, in the armeours manuals the distances are in meters and drop in centemeters..........

Go figure...... :headscratch:
bustr - POTW 1st Wing


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Offline FLS

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Re: a simple rule for gunnery range?
« Reply #16 on: March 15, 2012, 08:47:30 PM »
More high is your speed approach to the target, more less gunnery convergence must be.

It's right?

 :salute

Your speed relative to your target mostly just changes the timing of when you shoot.  If you set your convergence at max distance then there is a little more time to concentrate fire on a target but with a close convergence you are likely to shoot more accurately at the convergence point and may get more hits even with a shorter burst. I wouldn't change convergence for different mission profiles, it's best to get used to one distance. There are enough variables in gunnery already.