Please someone call me out on this if it has been mentioned before. Here's my design modification for the bolt of this incredibly simple marker.
Correct my if I'm wrong but the mechanics of this marker is basically an inversed Air Gun Designs dump chamber on Mags. Instead of the bolt plugging the hole in the dump chamber the bolt is sitting on the plug holding the air in the dump chamber. So theoretically the level10 bolt implement of having a very tiny hole in the bolt to vent gas out slowly as the bolt is traveling to prevent chops could be easily implemented in the G3 or any gun derived from this design. Here's the animation for the lvl10 bolt from AGD.
I don't think I'm crazy but maybe someone with more technical knowledge could either prove me wrong.