The stock looks like it composes half of the weapon's size. On an assault rifle or the LMG, it may not be the problem. The "Commando" carbines are traditionally designed to have a smaller profile, while having almost the same barrel length/range as it's "bigger brothers"-the assault rifle. Also, the piece in front of what looks like a sling's port, is that supposed to be a cheek rest? It looks too big. On modern sniper rifles they aren't usually so big. The buttplate of the stock looks really cool!
Maybe it's the wrong nomenclature I used, I used the german version. Like the G36c (Commando) is mainly a shortend version of the standard version, normally use for CQB. And yes it's a cheek rest and I made it this long that you don't have to "aim" for the thing with your cheek in a fast combat situation ^^