Not really an idiot, he is merely demonstrating the reliabilty and durability of an AK-47. An M4 barrel will start melting in under 600 rounds of sustained full-auto fire.
Of course it was on fire (at least the combustable parts are). If the barrel is not warped the steel has probably been at least partially annealed and won't last long. ...And he is an idiot, unless he has guns to throw away..then there is just the ingrained attitude of real riflemen that they don't want to utterly abuse a rifle !
Just how much an M4 or an Ak-47 will suffer from sustained fire of several hundred rounds is a moot point; anyone who would sustain fire anywhere near a hundred rounds, should have his head examined. Combat rifles are not designed to maintain anywhere near that kind of sustained fire. Rudimentary machine gun training explains the folly of such sustained fire, machine gunners are trained to time their bursts.
As far as the AKs being in any normal way "superior" to the M16 series, is very much open for debate. Right off the bat, the primary mark of a good rifle is it's inherent accuracy,.... where the AKs come off a distant second to the M16s.
While the AKs are a good and very serviceable combat rifle, their popularity, especially with insurgents and Pancho Villa type armies is for two main reasons 1) they are cheap to produce, with their stamped housings, and 2) The sloppy tolerances throughout the rifles means they will function well when they are terribly neglected...a plus point for a ragged and undisciplined force.
While the AK's 7.62X39 round works well for very close (room to room) operations..so too does the M4. The AK47 rate of fire is 600 while the M4 is around 950 (rounds per minute). The special ops Marines I know personally and who have been involved in such combat around Ramadi and Fallujah preferred and stuck with their M4s, when they could easily have used the AKs...actually they most often preferred the Mossberg 500 for that job.
Beyond 100 yards, the M16 takes over as to accuracy and ballistics...plus armored vest penetration, say nothing about the many special purpose accessories available for the M16 base.
One indicator of the quality difference; The armies who can afford them , the M16 is chosen over the AKs as their service rifle. They are willing to pay about 3 times more for the M16s.
For me, the watchword for rifle..should be accuracy, that is why so many varmint & long range coyote hunters use AR15s while few use Aks. Below is an interesting video featuring the well known Dr Atwater;
http://splodetv.com/ak-47-vs-m16