Took a front bead off of a fairly new 870 magnum today, with rib, and the threads were trashed. What gives? I didn't "horse" it off, and it felt like it turned off normally, but the threads are gone on the bead and on the barrel. I was wanting to put on a aftermarket bead, seemed like an easy deal, now it has to go to a real gunsmith and be drilled out bigger and tapped. Is there some trick to getting them off? What did I do wrong?

The beads are not threaded on the newer remingtons- I am suprised you even got it off, I just grind them flush, drill, tap, and screw in the new bead.

Duane,

No you can definately see threads on the bead stem and in the hole. It "felt" normal as I turned it out, it wasn't until the new bead wasn't threading in that I looked closer and saw the threads trashed in the hole, and saw them trashed on the bead. I'm just wondering if there is a "trick" that real gunsmiths know about on how to get them off without wrecking the threads? Still wondering if I did it, or if Remington overtightened it when they installed it?

Duane is correct.
On the 870 vent-rib shotguns, the front bead has always been pressed and cross-pinned in.
Just take it to your local gunsmith, and he will drill and tap it and install a screw-in bead.
I charge $11.25 plus cost of the bead in my store, but $15 would not be unreasonable for the labor.

-Spencer