Come to think of it, the stuff Bobby always sent may have been B50. I never took the time to tie an "adjustable" nock point. Just used a half-knot, wrap a couple times, nuther half-knot, etc. I always put a little dab of CA glue on it when I get it to the right size, and mine have lasted a long time.
Back to the "adjustable" part... I use waxed dental floss when tuning. Tie one off, tune, cut if off if adjustments are needed, and another is quick and easy. Once a new string is settled in and I've got it where I want it, then i switch to the string material. FWIW...