What is the military standard to disassemble the M16A2?

Answer 1

• Clear the weapon
• Remove the sling.
• (with the M4, XM177, M16A5, and other variants which have a collapsible buttstock) Remove the buttstock from the extension tube
• Remove the handguards (ignore this step if the rifle is equipped with an RIS)
• Push in the takedown pins
• Separate the upper and lower receiver
• On the upper receiver, pull back the charging handle to withdraw the bolt carrier assembly
• Remove the bolt carrier assembly from the upper receiver
• Remove the charging handle from the upper receiver
• On the bolt carrier assembly, remove the firing pin retaining pin
• Remove the firing pin
• Rotate the cam pin counterclockwise and pull upwards to remove it from the bolt assembly
• Remove the bolt from the bolt assembly
• Depress the extractor and push the extractor pin out (you can do this with the firing pin)
• Separate the extractor from the bolt
• On the lower receiver, depress the safety detent spring (I recommend you use the charging handle to do this if you don't want to pinch your fingers)
• Pull the buffer and buffer spring out of the extension tube
• Separate the buffer from the buffer spring

This is operator-level field stripping.