Try a wrapped on nock, Easy to do and you can get your tips as thin as you dare.
+1
If they are super de duper narrow, reflexed, and its a high weight bow, they can twist on you. For a longbow, with wrapped nocks, I have successfully pulled 3/8ths in oak, #75 or so at 28"
On a bow I made for my friend's little bro, it has 1/4th wide nocks, wrapped on... and pulls 35#@24.