27rds in a 30td M-16 mag, I perfer to start with 2 tracers then when I see a tracer its reload time. Pack out for the M-60 is 200rd opened, 200rds on the gunner, A gunner carries 600rds, B gunner carries 600rds and the tripod, rest of the squad 200rds. You hope for a 5 count, but throw on a 3 count and pray they cut the fuzes correctly. Dont know about C-rats, but MREs are 12 to a box, 36 lies in a box.