Had the same problem of poor arrow flight due to too tight of nock. I read paper by O.L. Adcock, “Tuning Longbows and Recurves”. In the section, “Thoughts on Strings”, he states on string break strength “The rule of thumb is a 5:1 ratio in string strength to bow draw weight. A 250 pound test string is adequate for a 50# bow. That’s about 6 strands of Dacron.” The article goes on. To sum up, I shoot 50# longbows. I now use a 12 strand Flemish string served with #4 serving material. Nocks on carbon arrows fit perfect, they snap on lightly, fall off with a tap on string and shoot beautifully. I also pad the loops to 14 or 16 strands just for fun and to protect against wear. I have been shooting 12 Dacron strands on 50# bows for about 15 years. NEVER had a problem.
