"high phosphorus" electroless nickel?

[jkellymcc]

I am interested in trying electroless nickel plating for some firearms and firearms parts. I have noticed that several of the platers who do lots of firearms work advertise their electroless nickel as being "high phosphorus" and suggest that this is some superior form of electroless nickel. Is this just marketing hype? Are there marked differences in the plated material from different electroless nickel processes? How does the Caswell system fit in terms of "high phosphorus"?

Thanks,
Kelly McCoy