I agree that FC looks really flat but I am no game developer and can't question them on what's going on. I have plugged in the numbers they give into a ballistic program that maps trajectory and found the closer the convergence the better. But in the end, were talking a few feet or a few inches difference.
How I figured my preferred settings and "confirmed" my ballistic findings was to repeatedly bounce AI aircraft again and again and again while switching the convergence around.
There's a video on it but you'd have to join the 103rd to see it.
You can always jump in one of those free tanks and fire off the MG42 and see the rounds drop too.
Hagar, yes. It will actually cross the boreline twice. Once closer to the muzzle end and then back out where you have your sight ranged at, in your case 1000m.
In that other game it definitely changes when you play with your convergence settings. In this one, I'm not sure that it does yet and I haven't ran the same test like in that other game.
Also, even if you have your sight convergeance set close at say 65m, there is another point out there along the boreline that the rounds will cross as it drops back down. Which may or may not be 300m.
Your mileage may vary.