Re: colt diamondback nickel vs electrolysis
moonboy, I will chime in here.
If you have a .22LR 6" in excellent condition with no box or papers, it would probably bring $1200 or slightly more in todays market. Now as for the same gun in electroless nickel, I have never seen one and don't know of any in existance. But never say never. If such a gun exists, I would think it would bring a slight premium over the high bright nickel as very few of any bore or length were done in EN. What I would be very very wary of is to make sure it is not hard chromed (after market), which looks a lot like electroless nickel, fakes are out there. If it is hard chromed, it might be worth $400-450 to someone as a shooter, but has no collector value.
HTH