Looks like it's a HEAT high-velosity stream.
Probably something like a long-focus HEAT charge we studied in college.
This type of anti-tank weapon uses a metal stream from a cummulative charge to hit a target at a distance, not when the shell hits the armour.
US has such weapons since 80s. They even had a disposable robot with one charge focused at several dozen meters. The charge looked like a searchlight on top of a tiny tank.
Soviet army had cassete anti-tank bombs with elements dropped on parachutes, rotating, scanning the surface, and when a heat detector sences a tank engine - this thing goes boom and sends a cummulative stream for 20-30 meters. Cummulative stream moves at impressive 7-15km/s.
For example: RPG-7 HEAT charge has a deep cummulative funnel, all the explosive is around the long copper cone that forms a cummulative stream. This is a short-focus charge, where the stream is dangerous at short distance (centimeters). A long-focus cummulative charge looks like a searchlight, with a shallow spheric cumulative funnel. The cummulative stream doesn't fall apart for dozens of meters at least.
IMHO it was a modern anti-tank mine, designed to hit a tank from the side. It was indeed a "golden shot".
Sorry for silly explaination, I don't know English terms.

I studied for four years to be a warhead designer, had to quit and didn't finish college

Now, back to my original repertoir
It was the second Abrams knocked out of commission by the enemy in Operation Iraqi Freedom. They lie as they breathe.
Arabian TV showed at least 3 burning M1s. Fourth one mysteriously "sank in Tigris". So three plus one makes one. I love this little military lies. "If you civilians are so clever - why don't you march in formations?" "In war time sinus can reach 3 and even four"...