It seems you are leading the field on this one.
Stop teasing us with this mystery, what do you think the potential benefits could be for the barrel?
How are you applying this WS2 to the barrel, how long does it stay treated?
I see that it comes in a high temp grease form...I might be interested in using for my brake retainer pins. Alternatively, adding a small amount of powder into the crankcase of my racecar...hmm. Only problem is how much passes through the filter and whether it completely clogs the filter, or reduces flow...nah.
Here ares some marketed benefits of nitriding (thanks for the correction):http://www.ahtweb.com/content.php?id=15&t=%3Ca_name=