You gotta admire the LEGO enthusiasts of being creative at making LEGO models of various real world products. In this case Kevin184 made an actual working LEGO model of the HK416C that is seen in the Ubisoft Tom Clancy's Rainbow Six Siege online multiplayer game. The retractable stock works and you can pull the charging and fire a LEGO projectile. Poor Minion, he had no chance against it.