the USAF green M-16 I carried had a selector switch for either ‘full auto’ or ‘single fire’. It was something, considerring the only rifle I shot before that was a Remington x40 single shot target rifle in.22 long rifle, as part of OtisAFB Junior NRA.
AR-15s are ONLY semi-automatic.Any designer of ‘assault weapons’ would be one huge grabassticlizardzit, were he to design single shot weapons only.
Unless I'm mistaken the AR-15 is entirely semi-automatic,as are many other rifles available today.
In '69 the M-16 was capable of firing a full clip with one pull of the trigger.Today I believe they're capable of three round bursts. Big,big difference. The US Armed Forces have absolutely no interest in procuring AR-15s.