http://trainers.hitechcreations.com/The sights found on the Panzer, M-8, LVTA4 and the Tiger simulate the gunner looking through an optical sight. The working part of the sight is the scale shown to the right. This consists of a center line and a scale showing various ranges in 100s of yards. This range scale adjusts depending on the type of ammunition you are using. Your sight also shows you the type of ammunition currently loaded (AP = armor piercing) and how many rounds of that type you have left (79). The [Backspace] key changes the ammo type.
The basic operation of the sight is simple: put the center line on the target at the appropriate range and pull the trigger. In practice, it is much more difficult.
Enemy ground vehicles do not show an icon or range information. This makes it difficult to determine range for your initial shot. While experience will help you make that initial range estimation, you can still get on target with just a few shots. As with the open sights, using your cursor is the key to getting results.
When a cannon fires, its recoil is strong enough to move the entire vehicle. When everything is finished moving, your sight picture will not be where it was when you started. The images below show a before and after sight picture from a stationary Panzer IV H. Note how much the sight moves after taking a shot. By taking a second or two to place your cursor on your target before firing, you have a ready reference point to adjust your fire from. Simply move the cursor back onto your target, then add or subtract elevation as necessary. The same goes for lead on moving vehicles.
sight picture before shot vs. sight picture after shot
The cursor also gives you a better aiming point when firing from a moving, bouncing vehicle. Once you are getting hits, fire when the cursor is on the target.
Hope this helps a little.