Placing the gunsight to the right off center was based on the idea that you would aim more naturaly if the gunsight was alined to your right eye. When you shoot a gun do you first hold it in front of you lined up with your nose then try to look through the sights with both eyes?
The 3 dots are a 10m wingspan at 300m. Half of that is 600m. 10m wingspan filling the ring is 100m.
All rings, dots and ticks in reflector gunsights for the germans and italians have to do first with determining range of your con based on the average wingspan of a fighter is 10m and a bomber is 30m. Then the outer ring is a deflection hold over gauge along with the ticks and dots used for bullet drop, lag lead and ordinance dropping.
You can test a 100mil ring offline for snap shots. At 400yds lead by roughly 1.5 100mil rings as the con is passing 90deg right to left. Place the edge of the first ring at your gunsight center. Then a second ring next to that. Pull the trigger when the con's nose touches the center of the second ring. That will work for the offline drones traveling at 250mph. At 300-400mph you have to add more lead to account for the increase in speed.
If the offline drones were traveling at 100mph you would only need to shoot when the cons nose touched the outside of your main ring. This is where the british term "100mph Ring" comes from in reference to the MkII gunsight. Revi and San Giorgio main rings are 100mil.
