In this image From the BBC, a militia leader makes sure that the PKM is up front and center. As in the picture of the Al Shabab marchers, it makes sense to put some of the more powerful weapons up front, to show that you are well armed, perhaps to intimidate enemies, or gain some political clout. This might be considered a local version of the Soviet May Day military parade. With both side and bottom shots of the soldier/militiaman with the PKM, the use of the feed box/ammunition box is clear. They are conspicuously lacking in the...