Trying to find out what this is?

I caanot for the life of me figuring out what kind of cartridge this is. Need some help. What I do no about it is this.

1) It states that it is a "SuperX .357 Magnum" on the bottom of the cartridge as all are the same.

2) I own 6 rounds

3) The truncated bullet does not attract a magnet. Tour one open and it has a large chunk of lead below what we see here.

4) Could it still be an AP round for those bad guys wearing vests?

5) I was given these rounds in the mid-1980's for a trade with my partner. He got the box of .45 caliber "Black Talon" that were ++. I am beginnig to think he may have gotten the best deal out of this one?

MAB32
Mark