1-6 Assemble the Rifle
Replace the sling.
Put the handguards in place.
Caution: Before closing the upper receiver group the rifle must be on safe. Close the upper and lower receiver groups, seating the takedown pin, and ensuring the selector switch is on safe.
Engage the receiver pivot pin.
Join the upper and lower receiver.
Push the charging handle and bolt carrier together in the upper receiver.
Slide the bolt carrier into the upper receiver.
Place the charging handle by engaging it, then pushing the charging handle part of the way in.
Pull the bolt back.
Put the firing pin retaining pin in the bolt carrier to seat it.
Drop in the firing pin to seat it.
Place the bolt cam pin by putting it in the bolt carrier turning it one-quarter turn.
Slide the bolt into the carrier until the bolt cam pin hole in both the bolt carrier and the bolt are aligned.
Push the extractor pin in.
Insert the extractor and spring.
Insert the spring and buffer.