Actually, atleast on western front, 50cal IS the most accurate weapon and has the greatest range, for example after 800m mk108 round dissapears, this does not happen with 50cal all the way to 1800m.
What does happen though, they are not that powerfull at greater distances, that's probably because...====NEWSFLASH====...physics affects the super holy mighty planet destroyer a.k.a. 50cal too and it too looses hitting power as it travels.
The only thing you might have on in-game 50's is tracer visibility, they are really hard to see comparing to other bullets/shells, but all those fairy tales in effort to really make them planet destroyers are hilarious
