I just bought some and I want to know how far to drive them. They are on a 15” cable and the driver is 24” should I mark 15” on the driver? Or drive them farther in? I’ve never used these before so I need a little helping

Depends on the ground. I drive mine, then I give them a good healthy tug to the side, if it's solid, I leave it, if it ain't solid, then I pull it and redrive it deeper, unless I can't pull it, then I leave it. Hope that helps.

I drive them in until just the loop sticks up in the bottom of the trap bed I made. I don't want any extra springing up out of the ground - that just makes it harder to bed the trap.

But if you are not putting them in a dirthole bed... if you are using them for a snare anchor or some other kind of land set, I guess you only need to drive them as deep as they will go or "deep enough".

I drive mine in up to the first swivel on the trap chain then give them a good tug to "set" the anchor.