Realism... in gun designs? TENNO and OROKIN gun designs? The same guns made by egotistical, gold gilded, sadistic, space magic wielding demi-gods who have to have everything gilded in gold and so over-engineered that even the Germans wouldn't use so many parts just to lock open the chamber (the Mauser C96 used a system of levers and locks to lock open the bolt, at least 5 to 10 pieces. the colt 1911 used a hook, 1 piece).
But i can understand it for grineer (to a degree) and corpus though. But rule of thumb for power fantasy, rule of cool, and realistic design takes a side seat.