One of the most common questions hunters ask me is, "How do I get broadheads to shoot straight?" Harvesting a mature whitetail is challenging enough without complicating the process with arrows that fail to hit where they are aimed. Nearly 50 years ago, I began bowhunting for whitetails. During the early years, I encountered frustration with broadheads that wouldn't fly perfectly. As time, equipment and my knowledge moved forward, so did my accuracy. I found that a well-tuned bow would shoot broadheads with the same success as target points.
Many hunters have discovered that a bow that executes target points accurately may not shoot broadheads with the same results. A hunting bow should be tuned to the arrows and broadheads that you are going to use in the field. Always tune the bow with target points of the same weight as the broadheads.
The arrow rest is a critical part of a successfully tuned bow. Most of the arrow rests on today's market will work for hunting. The one you select must allow good vane clearance, with a fairly low nocking point when the arrow is released. If the vane makes contact with the rest, it is impossible to get a good tune. The drop-away rest is my personal preference, because the arrow can be shot from a level-launching nocking point. Begin by using a bow square and placing the nocking point so that the arrow sits level or is nocked 1/8 inch high.
Next, make a rough set on the center shot of the bow. This is done by visually aligning the string so it passes through the middle of the base of both limbs. Place an arrow on the rest and view where the point is located. If the point is to the right of the string alignment, move the rest left or vice versa until the string cuts the middle of the point.
It is very important that the spine of the arrow shaft is of correct stiffness. By checking an arrow chart, you can determine the correct size. At this point, you are ready to tune the target points. If you are familiar with paper tuning, you can use that method. If not, you may want to use the French tuning procedure. This is done by going outdoors and sighting the bow for 8 to 10 yards. Then place an orange dot at the top of the target butt and shoot an arrow into the dot from that distance.
Leave the arrow in the target and go back to 35 yards and shoot at the same dot with the same sight pin. If the arrow appears to fly erratically, it is probably hitting the arrow rest. To make a correction, move the nocking point up 1/8 inch. With a clean arrow flight, the target points will hit low. If the low arrows are left of a perpendicular line from the top arrow, move the rest to the right. If they are to the right, move the rest left. Repeat this process until they are directly below the top group of arrows.
Broadheads basically fall into the category of fixed blade or mechanical. Mechanical-type heads should hit in the same place as the target point, whereas fixed-blade broadheads require further tuning. I prefer the fixed blade, because they have better penetration, especially when shooting through bone.
The blades on the broadhead can vary from 1 inch to several inches.