50 cal BMG penetration.

[InfernoMDM]

Can annyone add to this. The conversation was started over the use of 50 cal BMG rifles in Iraq penetrating most Armored vehicles.

Ahhh, but according to this video, featuring the instructor of the Scout/Sniper School for the USMC at Quantico, AP rounds are only effective out to 2000 yards. This I tend to believe when using the .50. I refuse to believe from my own ballistic tests and others conducted by the military, FBI, and ATF that a .50 rifle can do the damage to 19mm armor at 2000 meters that is being claimed here. They even show in the video and 1" thick piece of armor that was not penetrated by a .50 AP round. SLAP round, yes, but still under 2000 meters. And deflection does have quite a bit to do with penetration. All the targets show on the video were full frontal shots with minimal deflection. A 60-degree frontal arc defeats just about every non-SLAP round on the market today, military or not shot from any rifle.

Video:
USMC Scout Sniper Instructor School Terminal Ballistics Demonstration of the Barrett M82A1A SASR
http://www.biggerhammer.net/barrett/50calt1.rm

 

[Sunray]

"...most Armored vehicles..." Light armoured vehicles, maybe, but not most. A .50BMG will bounce off a tank. Especially the turret. The front of the turret on a T72 is 520mm thick.
You're dead on with the angle though. As I recall, 45 degrees was enough to double the effective thickness of the bow and side armour on W.W. II tanks. Mind you, 19mm is well under an inch thick. 25.4mm to an inch. Angling the plate will make the thickness a projectile has to penetrate an inch or more though. That's the whole point of angled armour. Same weight, but more protection.
You'll note that the only piece of armour plate mentioned was the first wee bit and no mention of the range it was shot at. Everything else was not armour at all. Just assorted steel targets. Ain't the same thing. He's also talking about light armour only.
7.62 ball will easily shred a cinder block at 100 yards. I've never tried it past that distance, but the block I shot up, doing a demo one time, had a piece the size of a slice of bread left in one piece.

 

[Double Naught Spy]

I think the quote is in error. The instructor did not say AP was only effective out to 2000 yards. What he said was that the fixed 10x Unertl scope allowed the shooter to engage maximum effective range armored targets out to 2000 yards. The statement seems to be one of denoting the limitations of the scope and not the ammo.