Here you go guys. Sorry it took so long, I shoot with a group of members here every Wed afternoon.
Keep in mind this is typically done with carbines that see a fairly moderate firing schedule. I have decided to adhere pretty close to this on a few of my guns. Some of my "fun" guns not so much.
Here is our PMS for the M4, the key is to prevent problems from occurring. I use this to keep track of where things are and to gauge the life of various replacement parts we use.
2,500 round interval,
Inspect and replace as necessary extractor spring, insert and O-ring
5,000 round interval
Replace extractor spring
Replace extractor insert
Replace extractor
Replace Crane O-ring
Replace gas rings
Replace action spring
10,000 round interval
Replace bolt
Replace lower receiver parts
15,000 round interval
Replace barrel