I noticed that not all my arrows shot bullet wholes through paper. But flipping over the ones that didn't worked . then i turned the nock so the location bumb was out , and bingo . i check all my arrows this way . I use 4 - 2 '' blazer Vanes on my 32'' arrows . Now every arrow shoots perfect out of my Hoyt Nitrum 34 LD . getting the spine lined up close on each arrow , did make a difference in my 300 arrows . good way to check the stiff/heavy side.