I just cleaned my brand spankin' new AR15 for the first time in preparation for my class this weekend. This was really the first time I have dealt with this platform. For those interested, here is the video series that helped me through it.
Cleaning the AR15 part 1
Cleaning the AR15 part 2
Cleaning the AR15 part 3
The question I have, especially for the military guys, is how the heck do you NOT lose those firing pin retaining pins and other small parts when you are disassembling it and cleaning it. I was reassembling the firing pin and lost the retaining pin. Eventually found it, but in the field, that must be a nightmare.