That's a frustrating mechanic. Lower end suppression values on the MG34 and vickers and probably now the maxim make MGs too weak vs an actually spaced blob. Any MG can suppress 5 units stacked ontop of each other, but when you need to suppress 2-3 that are spaced very quickly only the MG42 and 50cal can probably do it anymore. I don't count the DSHK cause it's doctrinal but it most definatly can suppress.
There is an incremental accuracy modifier, but as far as I know it's not used on any weapon, not even machine guns. The problem with it is it only considers model count and now squad count, which might be why it's not used. Target tables might be able to fix that, but they might not, depending on what they allow you to do.