Maximum Point Blank Range is an important concept to understand if there is ever the possiblity of you being in a fire fight or even targeted when fleeing.
5.56 rounds on average have 90 yard maximum MPBR
7.62 rounds on average can have an MPBR up to 375 yards.
Factors that effect MPBR include the weight of the projectile, its velocity and the ballistic coefficient.
NATO Military Forces are taught to engage an enemy at 300 metres or less while Sino-Soviet doctrine teaches a distance of 270 metres. Thus if you have an MPBR of 375 yards (approx 341 metres) you can engage a military trained threat before you are in their tuned range of engagement.
With the M16A2 Assault Rifle, every Marine is trained to shoot a body-shaped target up to 500 meters point target. Max effective range is 550 meters point target, and 800 meters area target (large object or crowd).
The standard ammo for the M16 is the 5.56mm ball round. I've heard talk about higher ups in the Corps wanting to go back to 7.62mm for the increased stopping power.
Of course, it's unlikely that you'll encounter any Marine Corps trained riflemen out there on the city streets. Most likely it'll be Army National Guard or private contractors such as Blackwater or KBR, whose shooting standards are more lax.
I heard a story of a bunch of Army Rangers trying out the Marine Corps' KT course of fire, and not one of them being able to qualify with a minimum score of 190 out of 250. I most recently shot 211, which is Sharpshooter.
Still, the M16A2/A4 or M4 Carbine are the weapons of choice.
You may also see the M9 Beretta. This is the military's standard issue 9mm pistol.
No offense against you or any marines, but the Ranger story sounds a bit far fetched. Granted, the average Marine is usually superior to the average 11B infantryman, but generally not on par with any ranger worth his tab, let alone any sf/so guys. Now marine LRPs guys are another story. Also, private contractors that I have had contact with are either completely incompetent marksmen or almost god-like in their abilities. Of course this is just my observation.
Look, it's not a matter of pride for me, because I'd just as soon be out of the Marine Corps. I heard that story from a Marine who worked on the rifle range and had witnessed said Army Rangers attempt to qualify on a Marine Corps rifle range.
The KT course of fire that the Marine Corps uses is much more difficult than anything that Army Rangers use.
I disagree with you there as well. Unless they have drastically changed their courses in the past 6 years, you are incorrect. I trained with marines, special ops, seal and rangers. There was very little difference in any training that revolved around the m-16/m-9/m249/m-60. Matter of fact, in Benning when the Marines were invited to a special sniping "seminar" sponsored by the 75th Ranger Batt, less than 1/5th the Marines qualified. But there were 2 of the Marines that beat everyone else there hands down at the end of the month, Rangers included. And by the way,I do agree that the KT course is a very difficult standard test.
Bottom line is generally speaking the very best marksmen are the civilians that fire their weapons daily for whatever reason. For every 5 expert qualifying Marines, you could find 10 hillbillies with a mouth full of chew that could do just as well or better.