One thing I try to do is shoot when the deer is taking a step forward(relaxed deer) When the deer moves the front leg closest to you forward it opens up the vital area, with the leg back, the shoulder blade is over most of the vital area. I try to shoot while the deer is in motion, thus the deer is already concentrating on finishing his movement before he can react. Only had a problem with this once. Last year, a doe was slowly walking past and when I shot she lunged forward and I ended up with a gut shot. We looked for 4 hrs and never found her, rancher did later that week. However the bow did make a little noise and I didn't get to practice that much last year. Bad combination all the way around.