The M16A2 buttstock is about five/eight" of the inch extended then the sooner styles. Due to the enhanced duration it used an extended buttstock screw and a spacer. The swivel is mounted closer into the buttplate. This buttstock is now used within the M16A4: The barrel is usually a 1970's https://dotcom-directory.com/listings12971371/the-colt-python-6-for-sale-diaries