RPG's and tankbusters
 

I was reading something the other day that got me curious. Some type of round penetrated an A1 Abrams tank leaving a hole smaller than a pinkie finger. The round went completely through the tank's armor and bounced around inside the tank before imbedding itself 2 inches deep. Here's where I read the article at Mysterious Round Disables Abram. The official release says it was...."just a lucky shot by an RPG." What do ya'll think?

My guess would be a Tungsten-core .50 cal AP round fired from a light fifty rifle. I've seen a training video for USMC sinpers, and the damage inflicted is comparable to what happened to the tank. It penetrated a 3-in piece of steel, then left chunks of metal embedded in everything behind it. The round left a hole about the size of a pencil, then fragmented.

http://www.sftt.org/PPT/article05242003a.ppt

check this out, pretty informative powerpoint presentation on the Abrams in Iraq. Some nice pictures in there too.

Nope...the Tungsten-Carbide cores of the Raufoss ammo wouldn't even dent the armour of an Abrams. You're talking about 2.5-ish inches of super-dense ceramic, plus .75 inches of DU, then another 2.5-ish inches of ceramic. Fifty-cal stuff just bounces off that stuff, as do the shells of all but one or two tank-mounted guns in the world. The 125mm gun carried by the T-80 can do it, and the Chinese have a 152mm in production that'll shred the stuff ( not sure of the designation ) but no man-packed or shoulder-fired firearm can penetrate it, and most RPG-type warheads just leave a big dent.
Several European companies ( Beretta is one, as is Solothurn ) are producing heavy-calibre rifles in 14.5, 15, 17, and 20mm, firing DU or Tungsten-Carbide saboted projectiles...it's possible that one of these, particularly the Beretta 15mm, could have done it, but unlikely.

.50 cal depleted uranium round perhaps? Or maybe like Selfdestruct said, a regular .50 cal.
The .50 was originally intended as an anti-tank round.

Besides a tank is actually a pretty delicate machine. It wont take as much punishment as popular media makes it out to take.

Where did the projectile hit?

It hit the weld between the hull and the deck, a classic softspot on a tank. From what I have seen and heard it was most likely a RPG-7V and a very lucky shot.