How would someone become a light machine gunner in the marines with an m240 m249 and or an m60?

if you were recruited as a 03xx and finished boot camp your next step is to got to the school of infantry. when i went through after about the second or third week you put your name on the list for 0331/ 0341/ 0351 and evaluated up until the fourth week when there was a split from the 11's and the weapons marines. your best bet is to talk to the instructor about being a machine gunner so he remembers you. as for being a medium machine gunner (m240b/ m240g) that is up to where your name falls on the list at the end. there is a 50/50 chance of being a medium machine gunner as there is a heavy (m2/ mk19). you can request to change if you wish but you will have to put in at least a deployment for that wish to be be considered. m60's have been phased out for 03's now everywhere i have been and the m249 saw is for 0311's.