I fully agree with Ducimus and completely disagree with Soopa typo not withstanding.
Stoner did not make the M16 Colt did.
The M16 had problems because it was rushed into service and was billed as self cleaning wepon which was never a claim made by Stoner or Armalite.Colt purchased the rights because they had the production capacity they are the ones that failed to have the barrel and bolt chromed which greatly reduces rust.The army can also be blamed because they by mistake or lack of understanding(it is not known which for certain) changed the powder to a type that was much dirtier than what Colt recommended.
Both rifles do have their place and contrary to popular belief the M-14 was not a trouble free weapon.In its natural role that of a semi-automatic rifle it performed well the M21 also performed well bridging the gap between a standard rifle and pure sniping rifle at the time M40(bolt action).
It also had another role that of squad automatic weapon to replace the BAR the M14A1.In this role it was an abysmal failure it was simply uncontrollable on automatic fire so much so so that the Army and Marine Corps removed this model from service.
On top of this nearly all of the early production M-14s had the automatic sear removed.You can ID an A1 because they have a weird looking pistol grip behind the trigger and also have a bipod and a funky looking fore grip as well as a muzzle brake with drilled holes rather than the slots of a standard M-14.
The M-14 in my opinion did not succeed fully in its intended role because it was simply uncontrollable under fully automatic fire.This role was failed by every western post war rifle because the 7.62x51mm round is simply to heavy to be controllable in an 8~10 pound weapon under full auto conditions.From a production standpoint it also to some extent failed because it was costly to produce.The DOD could not afford to fully arm the military with the M-14 many reserve and national Guard units where stuck with M-1 Garands into the 1970s.Part of this was do to the M-14 not being easy to mass produce.
One of the factor that proves that the M16 series
was in fact if properly treated a fine weapon is that many elite units in Vietnam who could choose the weapons they carried many of these guys choose to carry the M-16 or more commonly the XM177 sometimes called a Car-15.
I have asked my father this question many times as he was an LRRP in Vietnam and he preferred to carry the XM177 and he tried at different times
several firearms including the AK-47(90% of the time in Vietnam a Chinese Type 56) and even ANZAC FN FALS.He told me that the key was the typically range of combat and the weight of the weapon to him where the most important factors.And the XM was the lightest and most easy to quickly bring to bear it also had/has fewer steps(motions) in reloading something that your life might hang in the balance on.Weapon length is a huge factor as well at close range the longer you weapon is the slower your movement will be.
The other huge factor especially in Vietnam is weight the weather is brutal there and you really feel all that gear that you hump so more weight is always a negative when you have other options.
In modern combat the environment changes it can go from urban where a larger heavier rifle is a disadvantage to a more open one where you can use the benefit of a larger caliber.That is why you see the variation in weaponry most troops will carry an M-4 but you have some that are carrying a heavier DMR weapon it might be an M4/16 with a heavier barrel and also firing heavier grain rounds or it might be an M14EBR or one of the other modern variations of the M-14.The way I see it the M-14 in its modern forms gets to shine while in the past it was forced to be the jack of all trades a role that no firearm can truly fulfill.
Furthermore unless you have really put a lot of time on the range with both the M-16 and M-14 you really cant say which one is better for
you.And the question of what is better for an armed force I have already answered.Not trying to knock you Soopa but for many people even big guys the M-14 just does not fit their needs.
Stepping off of the soap box now.
@Ducimus They look like M-14s to me
was that some sort of trick question?