I'm being honest here. What's the thing with

[oneshooter]

84. There were several problems with the early M16a1

From Wiki:In 1964 when the Army was informed that DuPont could not mass-produce the nitrocellulose-based powder to the specifications demanded by the M16, the Olin Mathieson Company provided a high-performance ball propellant of nitrocellulose and nitroglycerin. While the Olin WC 846 powder was capable of firing an M16 5.56 mm round at the desired 3,300 ft (1,000 m) per second, it had the unintended consequence of increasing the automatic rate of fire from 850 to 1000 rounds per minute. This would leave behind dirty residue, making the M16 more likely to have a stoppage. The problem was resolved by fitting the M16 with a buffer system, slowing the rate of fire back down to 850 rounds per minute and outfitting all newly produced M16s with an anti corrosive chrome-plated chamber.[36]

The M16a1 was self cleaning, if the proper powder was used.

The aluminum barrel and the aluminum over carbon liner barrel were both dropped in 1960. The 4140 steel barrels and chambers were chrome lined in 1965.