Posted on October 23, 2012
Accuracy is in the details when it comes to selecting a modern-day drop-away rest
It wasnâ€™t that long ago really, perhaps 2004 or 2005, when the most common arrow rest was made of two simple metal prongs, or some variation thereof. It wasnâ€™t very tunable, had no arrow containment capability, fletching clearance was difficult to achieve, and it wasnâ€™t very forgiving with aggressive helical, which caused accuracy issue. But we didnâ€™t know any better at the time.
Then, shortly thereafter, along came the drop-away arrow rest. The prong rest went the way of the dodo bird and took its shortfalls with it. The arrow rest standard has since been forever changed, and for the better.
Now, the choices are mindboggling! There are drop-away rests of many different configurations, some rather simple and some very complex. Some have certainly raised the accuracy bar, but of the myriad of choices, which are the MOST accurate?
All drop-away rests are essentially inertia driven, but how they harness that inertia divides them into two distinct classes: cable driven and limb driven.
Cable-driven rests have the actuator cord most commonly attached to the downward cable, although there are a few on the market that work off the upward cable too. Regardless of which cable the cord is attached to, they both work essentially in the same manner. The cord is either served into, or clamped onto, the cable. As the cable pulls away from the rest, the cord is drawn tight and the launcher arm is pulled into the up position.
And thereâ€™s the rubâ€¦with such a design, the cable must pull the actuator cord with enough strength to draw the restâ€™s internal spring backwards. Doing so allows the spring to coil up sufficiently so that once the bow is fired, the launcher can recoil back in time to clear the arrowâ€™s fletching. It must be a fairly strong spring to achieve full clearance. Because of this, there must be some serious tension applied to the actuator cord to bring the launcher into the full up position and hold it there. This tension then pulls back on the cable and can, in effect, retard the camâ€™s timing. With incorrect cam timing you will not achieve level nock travel after the bow is fired. Tuning with uneven nock travel can cause serious frustration, even hair loss and heartburn! Accuracy is bound to suffer.
Fret not, however, ye current fans of cable-operated rests. There are some designs (Ripcord, QAD, AAE DOA) that have an internal sear, where the rest launcher is cocked and locked into the up position. This sear holds the launcher up, rather than relying on the tension of the actuator cord to keep it up. As long as the cord is the proper length and not too short, the sear will hold the rest up without pulling on the cable too much and effecting cam timing. Of the cable-driven rests, Iâ€™ve found the types with a sear mechanism to be easier to tune and generally more accurate. If your rest does not have a locking sear, just make sure that the actuator cord is the precise length. It cannot be too short or too long or you will have timing issues.
Furthermore, with many cable-actuated arrow rests, there is often a bounce back effect which one needs to be cognizant of. This is not something you can see with the naked eye, but slow motion video will often reveal a bouncing launcher arm after it makes impact with the riserâ€™s shelf. Because the actuator cord fully slacks off once the launcher arm falls, there is nothing but a little spring tension to hold the launcher down to the bowâ€™s shelf once an arrow is fired.
To address this, look into an arrow rest such as the Ripcord or QAD Ultra-Rest that employ an internal brake to eliminate the bounce-back effect. Based on my experience with the Ripcord, it works as advertised and is sufficiently accurate. If you shoot a cable-driven rest without an internal brake, be sure to conduct a fletching clearance test periodically with some lipstick or foot powder spray to rule out any contact.
Limb-Driven Rests: Best of All Worlds?
And if youâ€™d rather not deal with the fickle nature of some drop rests, look no further than the limb-driven rest offerings available today. With minor differences, these rests all operate in the same manner. The internal springs of limb driven rests operate in reverse compared to a cable-driven rest. Rather than the launcher arm being held up by tension on the actuator cord, the arm is held down. The launcher arm is not activated by tension on the cable; rather, it operates off the energy stored in the bowâ€™s limb(s). This brings about several advantages.
First of all, such rests are very easy to set up. One only need to bolt the rest onto the riser, initially tune with the launcher in the up position (which is the static position), then install the actuator cord and pull it tight enough so that the launcher arm is in the full down position. Thatâ€™s it. You are done timing the rest. You will have complete fletching clearance, and because there is nothing pulling on the bowâ€™s cable, there are no cam timing concerns either. You will have perfect nock travel every time.
Additionally, because there is tension on the cord with the rest in the down position, by design, the launcher is held snug to the shelf after firing an arrow. This greatly reduces or eliminates launcher bounce back. Arrow flight is always unobstructed. You can test for vane clearance if it makes you feel better, but my experience since using limb driven rests has shown that doing so is largely unnecessary. Â The can of foot powder spray in my medicine cabinet now only gets used for its originally intended purpose.
Lastly, because the limb of a compound bow stores such an extreme amount of energy, it makes for a much faster-moving attachment point than a bowâ€™s cable. Because the limb moves so fast, the rest can stay in the up position longer, dropping out of the way only at the last second. This gives the arrow more support during the launch cycle. More support means more guidance throughout the shot stroke and ultimately, more accurate arrow flight.
I also much prefer arrow rests with a spring-steel launcher arm. Spring steel has flexibility and gives more during the shot cycle than a rigid metal or plastic launcher arm. It flexes with the arrow as it is fired. This results in more forgiveness and ultimately greater accuracy. One only need to look at the best target archers to see that they prefer the spring steel â€œlizard tongueâ€ type of rest for the reasons I just mentioned. Fortunately, we can have these same advantages in a rest made for hunting. Both the original Limb Driver and the AAE Pro Drop are limb driven rests with spring-steel launchers.
Now that we have examined the pros of limb-driven rests, I would be remiss to leave out the cons. The problem is â€“ I just canâ€™t find any, at least not any legitimate ones.
Then the oldest criticism of limb-driven rests was aversion to the long actuator cord that attached to the limb. Bowhunters were at first resistant, thinking that such a long cord would get hung up on brush and damaged. I think this theory has been debunked as time has passed. I donâ€™t seem to hear that comment much anymore. Iâ€™ve hunted with a limb driven rest for four years and have hauled it through a myriad of thick and grabby brush from Arizona cat claw to the ubiquitous Colorado oak brush, and the rest cord gets hung up no more than your bowâ€™s string and cables. And you certainly canâ€™t do without those!
AAE also improved the design on their Pro Drop rest by using a stainless-steel cable for the actuator cord. Itâ€™s virtually unbreakable, and will not stretch out. Itâ€™s made the system virtually fail proof.
With those ill-perceived negatives behind us, one begins to truly see limb-driven arrow rests for what they are: a superior system! Sure, the cable-driven rests out there are perfectly serviceable, but if you want to take your game to the next level, a quality limb-driven rest might be just the ticket. With the ease in set up, consistently reliable vane clearance, lack of cam timing influence, greater arrow support, and the availability of spring steel, has the limb driven arrow rest proven itself as the most accurate type of rest available today? Of course, only you can answer that.
By Nate Treadwell