Our G22 built by AI fire .300 WInMag (7.62mmx67), which gives it more range than the standard 7.62 NATO.
Actually the usage of DMRs in the German army is somewhat dubious. We don´t have any official order on how to equip and use DMRs. For example each Jäger Kompanie (light infantry) has a group of snipers, who can be equipped with G3s but except for that I haven´t found anything official that regulates DM. AFAIK the infantry units in Afghanistan simply took G3s they had in their depots and use them now in squads, but how many are used and what other weapons these DM carry, I can´t tell. Judging from photos I´ve seen it looks like they carry only G3s, but that´s just a guess (not that you´d need yet another gun that weights you down! ^^). Too bad I´ll never go to Afghanistan so unless someone has some first-hand experience we can only interprete what we see on photos.