You missed my question - how do you know how reliable the M16/4 is and how do you know how accurate the AK47 is? But first, let's address your issues...
Less ammunition or lesser
ammunition? Black Hills Mk 626 is what the Marines use and we can definitely buy it. Performs a sight better than M855 too. If you're talking ammo cap, we can buy any 30 rounder STANAG mag out there. When 40, 60, and 100 rounders are available we can buy those too. Oh and, C-Mags are available, as well as SAW-MAGs.
The only difference between a military rifle and a civilian rifle is the trigger group - true. I never disputed this, but good job knowing that M16s and M4s aren't sold to the public. Here's a fun fact - you can purchase the same lower used in the M4. In fact, you can purchase everything used in the M4 from Colt Mfg except for the trigger group. HUGE difference, I know. But either way, the gas system is exactly the same -
Which brings up my point. ARs are reliable and AKs are accurate. For the AK statement let's go with a circumstantial scenario - would you stand in front of a man firing an AK at you at 100 yards?
For the AR reliability issue let's start by going through why it was unreliable.
1. billed as "self cleaning" which is patently wrong - fixed by telling soldiers to perform proper maintenance.
2. bad ammo - the powder used early in the Viet Nam war gummed up when exposed to moisture. This caused a lot of squibs. - fixed by switching powder type
3. excessive fouling - fixed with chromed chambers and bores
4. tilted followers - fixed with anti tilit followers
5. fouled - not fixed when maintained by negligent owners or troops. Fixed otherwise.
There's a famous Bravo Company Machine made AR that's run thousands of rounds and been cleaned once. Still running strong. Oh right, it's not an M16... but it has EXACTLY THE SAME GAS SYSTEM.
And finally, here's a good place to start looking for M16/M4 reliability:
To the rest of OCN: sorry. Had to rant against this ignorance.