If the nocks are too loose or too tight, stick them in a pan of boiling hot water and heat the nock. Not the shaft!! Snap the nock on the string and let it cool. If they are too loose to begin with. Heat one then pinch it closed a little and let cool. Then heat it again and snap it on the string to cool.wolfman_73 said:Thanks guys. I will go with the large groove and see. Like I said it's on a stock mathews string. Sorry Mike, but the wife likes to see em sooooo...they gonna be white. I have no doubt that the large groove will fit, just didnt want it to be too loose.