Various comments on this from SOH posts
"Open the folder of the aircraft, click open the xdp file which will open as a text file, near the top the guns are listed you will see may things Up, down, right and left limits and then the "rate Limit" This dictates how fast the gunner can move, lower the figure for the rear gunners as I am sure you have noticed it is only those boys that are NRA sniper grads.
I have reduced mine to 07, but since my planes in BoB are all ACE, they are still killing me so have went to 05 and still. I have opened up the German formation from .6 to .9 (1.0 is stock) and all those things make it possible. But, that only covers their ability to track you. If you stay in one place you will be hammered. So you must keep moving as they are not ducks at the county fair, they mean you bodily harm.
Remember afte clicking file and then save on your modified xdp file to delete the BDP file in the AC folder as that is the computer's version or translation of the xdp file. It will make a new one to read the info and allow the new change when you restart the game."
Various
"The sniper gunners are easily fixed. In the gunstations for the aircraft xdp, I tend to set the ratelimit for trainable guns at 12-15. IIRC that is the "rate" in degrees in which the gun pans in a second. It is not the rate at which the gun fires - that is set in the gun.xdp not the aircraft xdp. there is the occassional reference to "rate" in the gunstations of an aircraftxdp; AFAIK this is an error. For "wusses" that ratelimit number can be lower.
But also in the specific turret gun, the "timealive" in the gun xdp should closely match the range for the gun. Hence if the range is 700m and the gun's muzzle velocity is 750 m/s then a timealive of 1.0 seconds would be just about right.
Too long a timealive and the gunners open up too early/ or at least are effective too far out. The "Rate" for the machine gun is a bit more problematic, IIRC some are high to compensate for the CFS3 effect so I have no suggestions for that parameter.
Another trick to get rid of the sniper gunners is the "noise" parameter in the gun files. It has nothing to do with sound, it's the value for the bullet spread. Set it to something like 5 instead of the default 0.2 and the gunners will spray like always but they're not hitting anything except by pure luck.
Good catch Rene, I forgot to mention noise! If you look at the AvH gun xdps, the ones with _hand_held on them have a higher noise than the ones without. Eg. IIRC He-111 had the hand_held guns with a basic swivel. by the other token, I suspect the AvH guns in a _power_turret would have a lower noise. "
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Basically lower the rate limit on trainable guns; won't work with fixed guns.