Not wanting to step on any toes of those who do obtain nock fit by altering nocks,but
I posted in the shooters forum on this very subject earlier tonight. Have to agree with Steve and Jason about using the right diameter serving.
A while ago I was helping a friend with his shooting and after a few changes his form was solid and the guy was a national level pistol shooter, so I knew he understood focus, but somehow his groups were as good as I thought he could be shooting! Did a lot of filming and I only became more frustrated in the fact I couldn't find a reason why he wasn,t shooting better. OK, I thought, lets recheck his tune and surpisingly his bow wasn't even close to being tuned...while standing there scratching my head, I looked at his bare shaft and it appeared the neck ears were out of line with the shaft.....after setting up an arrow spinner and a dial indicator, we found that most of his arrow had nocks with the ears out of center, some as much as.015 out, which would amount to making arrows another .015 crooked...seems he had been heating his nocks in water and closing them to fit....and after changing all his socks he began to shoot groups more inline with his ability. Later I got to thinking...OK he just wasn't careful enough when altering his nocks, so I tried my best to close the ears and keep them in line with the centerline of the shaft....I did better than my friend, but not by much! I'm not sure a nock can be filed or sanded Exactly the same amounf on both side's and the same from one nock to another.