August 03, 2022
There’s no deeper rabbit hole in archery than bow tuning. If you don’t believe me, visit a dozen pro shops and ask for their best bow-tuning advice. You’ll likely get a dozen different answers, and the crazy thing is, they are probably all right!
Truth be told, the quest for a perfectly tuned bow is never-ending. Think about it; the performance of each bow is determined not just by the bow itself but by the bow’s interaction with multiple accessories, including the bowstring and cables, arrows, arrow rest, bow sight, peep sight, stabilizers and more. Change any one setting on the bow or an accessory and you’ve changed the bow’s tune. Did your string stretch? Well, your bow’s tune changed. Did your peep sight slide up in your string? Your tune changed. Did you bump your arrow rest just a smidge? Your tune changed. Did you get different arrows? Your tune changed. And on and on it goes.
Now, add in the human factor with a shooter who is susceptible to form variations from shot to shot, and it’s no wonder a bow that is “perfectly tuned” one day may seem anything but the next.
Fortunately, today’s bows are more consistent and tunable than ever, and you don’t need to be a techno wizard to shoot well. In fact, heeding even a handful of tried-and-true tuning tips will put you well along the path to success. Here are four worthy of consideration as you prepare for fall hunts:
1. Shoot Stiffer Arrows
Whether driving a sports car or shooting a bow, there is a very real temptation to take speed to extremes. After all, both car and bow manufacturers use bold claims to market their products, and if you plunk down your hard-earned money for something capable of going really, really fast, well, by golly, you want to feel the thrill!
Unfortunately, driving a car at breakneck speed can have disastrous consequences, as can shooting lightweight arrows in an effort to maximize the speed of your hunting bow. Every arrow shaft has a “spine” rating that refers to the stiffness of the arrow. The stiffer the arrow, the heavier the spine, and the more flexible the arrow, the weaker the spine.
Lightweight arrows tend to have a relatively weak spine, meaning the arrows flex more easily. When a weak-spined arrow is shot from a compound bow with a high draw weight and high-energy cam system, that arrow will flex wildly, resulting in erratic flight and poor accuracy. In extreme cases where arrows are severely “underspined” for the bow, it can lead to arrow failure, bow damage and even personal injury for the shooter.
Bow-tuning guru Travis “T-Bone” Turner, who along with Michael Waddell and Nick Mundt forms the famous Bone Collector trio, avoids those pitfalls by shooting heavier, stiffer spined arrows from his hunting bows and recommends others do the same.
“Speed sells, and a lot of people go down that road of trying to get faster and faster by choosing too weak of an arrow, spine-wise, and that makes it hard to tune,” Turner said. “I’d rather my arrows be way too stiff than not stiff enough.”
In addition to flying more accurately and consistently, Turner noted stiffer-spined arrows have added weight (mass) that allows them to soak up more energy from your bow, resulting in a quieter shot with less vibration. Equally as important, Turner noted, that added mass will help the arrow track truer through the wind and maintain more energy in flight for increased penetration into the intended target.
“I’ll gladly give up 20 fps in speed for a quieter arrow that flies better through the wind and gives me more penetration,” Turner said. “At the end of the day, accuracy and forgiveness are key. A slow hit is better than a fast miss, and if your groups tighten up even half an inch, that’s a lot in the scheme of things.”
2. Tune Your Cams
The design and build quality on today’s hunting bows are amazing, so it’s rare to find a rig with a truly jacked-up cam system. Still, your bow needs to be tuned for you, and taking the time to address any issues with cam timing and/or cam lean is definitely worthwhile if you want to maximize accuracy.
Most of today’s top hunting bows feature dual or hybrid cam systems designed so the top and bottom cams reach full draw at exactly the same time. (Note: Even single-cam systems are designed to travel a set distance that matches your draw length, so don’t think this topic is unimportant if you shoot a single-cam rig.)
If the cams on your bow are not in sync, one cam will reach full draw sooner than the other. This will cause imperfections in your vertical nock track and also make it very difficult to anchor consistently at full draw because one draw stop will hit the limb or cable before the other. Creeping just a little bit on one shot and pulling just a bit harder into the back wall on the next will result in variations in your arrow’s point of impact — not good.
“The two cams are meant to work together, and cam synchronization is critical for good, consistent shot groupings,” said Brian Glenn, co-owner of Archery at the Glenn in Allentown, Pa. “Fortunately, it’s not that hard to do. You just have to tinker with it until you get it just right.”
Whenever setting up a new bow or tuning a used one, Glenn checks the cam timing on a draw board. If it is off, he corrects the issue by adding and/or removing twists from the cables until the cams move in harmony. Even then, Glenn said, additional fine adjustments are sometimes required because the shooter’s hand pressure on the bow grip, wrist position and even hand torque can cause slight variations in cam timing. The key, Glenn said, is having someone else watch the cams while you shoot and make sure the perfect result you saw on the draw board is duplicated while you shoot. Like so many other aspects of bow-tuning, it seems perfect cam timing is shooter-dependent.
A final note regarding cam timing is that once proper timing is set, you must check the position of the nock set or D-loop to ensure it is aligned with your arrow rest, since adding or removing cable twists to adjust cam timing will move your nock point slightly up or down the bowstring, depending on how you are adjusting the timing.
Once you’re confident your cams are perfectly timed, you’ll want to inspect them for cam lean. The goal, of course, is for the cams to remain perfectly centered throughout the draw cycle and shot, as any sideways lean means side-to-side string movement upon release and erratic nock travel that will reduce accuracy.
As with cam timing, it is rare for today’s cam systems to exhibit severe cam lean, though even moderate lean can cause issues. The good news is fixing cam lean is often a simple matter. For example, in many cases a leaning cam can be brought into proper alignment by adding or removing a couple twists from the split yoke of your cable. And on Bowtech’s innovative DeadLock cam system, you can move the cams left or right along their axles with the turn of a screw. Other manufacturers, however, require the use of axle-mounted shims to adjust cam position, and in these instances, Glenn highly recommends seeking assistance from your local pro shop to avoid further problems, or possible damage to your bow during the installation process.
3. Paper Tune Your Rest
If you’ve ever noticed your arrows fishtailing as they come out of your bow and speed toward the target — and honestly, we all have — that means the arrow isn’t coming straight off the bowstring and your vanes are working overtime to stabilize its flight. Not only does this erratic launching action degrade accuracy, it wastes energy better directed at your target.
Paper tuning is a great way to improve arrow flight, and assuming your cams are already tuned as described in preceding tip, you can typically accomplish the mission simply by looking at the tear marks your arrows make in the paper and adjusting the vertical and/or horizontal position of your arrow rest accordingly.
In order to paper tune, you’ll need some kind of frame to hold the paper while you shoot. Your local pro shop likely has a paper-tuning frame you can use for a few bucks. You can also rig one up yourself using a spare cardboard box or purchase an inexpensive kit such as the Paper Tune-It ($14.95 | 30-06outdoors.com).
Once you have your paper in the frame, simply place it in front of a target and shoot though it from three to five feet away. Make sure there is enough room between the paper and the target for the arrow to pass completely through, and also make sure you are shooting straight into the paper rather than at an angle.
After shooting, examine the hole made by your arrow shaft and vanes and move your arrow rest accordingly. If your vanes are tailing to the left, move your arrow rest to the right. If your vanes are tailing right, move your rest left. If your vanes are tailing high, raise your rest. And if your vanes are tailing low, lower your rest.
In cases where you have multiple issues to correct, such as your arrow tailing low and left or high and right, first fix the vertical tear by raising or lowering your rest and then fix the horizontal tear by adjusting the rest’s left/right position.
As you are working through the process, Turner said, you shouldn’t worry about moving your rest too much. After all, you can always move back in the other direction. “I’ll move it hard one way, because I want to see results,” he said. “If the paper is responsive to me moving the rest, I know I am going to find a good place eventually.”
At the end of the process, you should be able to shoot through the paper and see a perfect “bullet hole,” or the circular outline of your shaft in the middle, with each vane making a small slit as it passes straight through the paper.
One last note from Turner; sometimes, you make adjustments to your arrow rest while paper tuning but just can’t seem to solve the problem. If that’s the case, he said it’s almost certain you are either shooting arrows with too weak a spine for your bow (more likely) or imparting severe hand torque on the grip as you shoot. So, try switching to a heavier arrow as described in our first tip, and have someone watch your bow hand closely as you shoot to ensure you aren’t giving the riser a death grip.
4. Level Your Bow Sight
Most bowhunters know leveling the second and third axes on their sights is important for maximum accuracy. However, I am convinced most of them don’t bother to do it. That’s too bad, because it’s not all that hard, and having your sight properly calibrated is critical if you want to make an accurate shot when shooting at long ranges and/or steep angles — both pretty important in bowhunting situations.
Before calibrating your sight, a quick explanation of the first, second and third axes is in order. I think one way to help you understand quickly is correlating them to the aeronautical terms pitch, roll and yaw.
The first axis on your sight is equivalent to pitch, such as when an airplane lifts its nose up or points it down. On your sight, this would equate to spinning your pin housing top over bottom or bottom over top — rotating either toward you or away from you if you are standing behind the bow.
The second axis on your sight is equivalent to roll, such as when an airplane dips one wing and causes the other to rise. On your sight, this would equate to your sight pins rotating clockwise (right) or counterclockwise (left) when standing behind the bow. If your second axis is not properly aligned, your aim will be off in the direction the pins are rotated, and the margin of error will increase as shot distance increases.
The third axis on your sight is equivalent to yaw, such as when an airplane turns to the left or right even though the wings may remain level and the nose doesn’t move. For this axis, imagine a vertical line through the center of the airplane and the plane spinning left or right on that axis. On your sight, this equates to your pins either pivoting in closer to the riser or pivoting outward further away from the riser. If your third axis is not calibrated correctly, your sight’s bubble level will “lie to you” (not be accurate) when shooting steeply uphill or downhill, causing you to tilt your bow even though you think it is level. As a result, you will miss in the direction your limbs are tilted.
Most compound bow sights do not offer first-axis adjustment. Rather, manufacturers build them to mount level when attached to your bow. Calibrating your sight’s second and third axes requires you to orient your sight’s bubble level using additional horizontal and vertical levels as a point of reference. There are a variety of ways to accomplish this task while the sight is mounted to your bow. However, it is far easier to do by taking the sight off the bow and leveling it with the aid of a specialized tool such as the October Mountain Products Axis Sight Leveler. Such tools make it easy to make second- and third-axis adjustments in mere minutes, allowing you to then re-attach your sight to your bow and shoot with complete confidence, regardless of shot distance or angle, so long as you check your sight’s bubble level to confirm your bow is level prior to releasing the arrow.
For more information about sight leveling with the Axis Sight Leveler, refer to my Field Tested product review here.