You said in an earlier thread that the guns on a B17 never actually "converge" at the point you are aiming at.
I did a little testing of the guns offline, using the .target command. I do not have screenshots of it, but it is fairly easy to replicate. I tested both the Lanc and the B-17 (although the Lanc was easier since the Nose and Tail guns both have more than a 180 degree firing arc and can thus fire at the same target).
I found the Lanc to be the most interesting of the two, for this reason. I don't know how long the Lancaster is, but assuming the bullets fire in parallel lines, there should always be two clear areas of impact on the bullseye (so if you fire the nose gun at a 90 degree angle, the tail gun will also fire at a 90 degree angle).
At 100 yards, there was. There were two easily discernable areas of impact, and there was no overlap. The distance between the closest edges of the impact areas was 3 circles wide.
At 300 yards however, the main areas of impact were closer. The close edges of the impact points were only 2 circles apart.
At 500 yards, there was one impact area. There was not two seperate impact areas that to me would indicate two guns set 60 feet apart firing parallel to one another.
This behaviour could concievably be explained away by saying that there is obviously some deviation in the path of the bullets that are fired out of the machineguns. Could a ballistics expert tell me how wide the "beaten zone" (I know that is the term for ground MG's, not sure if it applies to air MG's to) would be for a target at 500 yards? Also.. the circles on that target are in yards, or feet? I know it is 10 units of something, cannot remember the measurement.
Anyway, assuming the circles are in feet. At 100 yards, there are clear impact areas where at least 95% of the bullets hit. I would guess that the area is perhaps a circle with a diameter of 2 feet or so (just based on my observation of the pattern on the .target). These impact areas are seperate for the nose and tail, and are 3 'circles' apart from one another. If the circles are in feet, the distance is 30 feet between the close edges of the zones (which are actually seperate for each barrel at 100 yards- you get 4 very small, very dark blobs).
At 300 yards, you still get very clear impact zones, but they have somehow moved 10 'units' closer together. Also, the twin barrels of each turret have merged into one impact area. Would some sort of deviation from the normal (parallel, straight) firing line somehow account for the fact that the area where the majority of the bullets hit have moved 10 feet (or yards) closer together?
Furthermore, at 500 yards you get one large impact area. It is no longer possible to tell that the turrets are on opposite ends of the bomber (at least I couldn't tell, there were definately not two seperate impact areas corresponding to the two seperate turrets). Again, could some "spray" effect be taking place here that makes the majority of the bullets fired from both turrets land in the same area?
The B17's results were not as clear as the Lanc's results were, in part because I could not isolate two guns that were a significant distance away from eachother to get the same sort of results. However, I did notice the same pattern- at 100 yards there are clear and definable areas of impact for each seperate gun, at 300 yards there are still multiple areas of impact, at 500 yards there are no longer multiple areas of impact, just one larger one.
Could some ballistic's experts (Tony, and I know there are others out there that know far more than I do) study this and perhaps attempt to replicate it? Is there an explanation other than the one that I have put forth? That being that the buff guns do NOT, in fact, fire in parallel lines, but do in fact converge at a range that I do not know, but looks to be somewhere around 500 or 600 yards.
Anyway, just looking for some clarification on this issue, thanks in advance.
[ 10-30-2001: Message edited by: Urchin ]
