If you are making the transition from gun to bow, the most important thing you have to learn is where your arrow entry points are with the as opposed to a gun. These all depend on the angle that the deer is presenting to you, and IMO is one of the biggest challenges in bowhunting as opposed to firearm hunting, next to getting close.
Here's a classic example......
You're on your stand with your rifle/shotgun. You see a deer approach you on a quartering to angle. He stops at 30 yards. The next few steps he will take will put him into heavy cover or into a gully, so this may be the last that you have an open view of him. Now I've been in this situation many time with the gun, and you simply shoot right through that front shoulder and drop him.
Now put a bow in your hands, and reduce the range to 20 yards. What do you do? Well, what I would do is let him walk, because in order to hit the vitals on that shot, your arrow entry point has to be dead-on the front shoulder, and if you've boned out a few deer shoulders the reason is self explanatory, or should be. This also why with the bow you should always wait on a broadside shot until the deer's INSIDE front leg is FORWARD of the outside leg, or at the very minimum even with it. If the inside leg is behind the outside leg, then you are shooting through shoulder again.
One more example..............
You've been shooting 3-D targets. You know where the kill rings are. Now put yourself on stand with a bow, and imagine a deer coming in to you, and then angling away from you at 20 yards. Where to you want the arrow to enter the deer so that it will pierce the vitals best? If you shoot at the "kill ring", you will most likely NOT have good killing shot. In a cse like this, you actually have to aim for the last rib or even behind that so that the angle of the arrow is dead center of the vitals when it passes through the middle of the deer.
Bowhunting.......the "thinking" man's game! [;)]
Offer No Apologies.....
NRA Endowment Life Member