Perhaps somebody with a complete and original specimen could get some measurements for you?

If it ain't right it has got to come off the barrel. Otherwise sight bed inletting and handguards will be off. If Bubba put it on there without a cross pin, he might have soldered it, yes.

Don't force it Lou. Be gentle. Get oxy acet torch and the FBH.

I'd be itching to see what is under there. I think that Bubba might have draw filed the barrel and reinstalled the base. You need to measure and compare diameters.