Which Drop-Away Arrow Rest Design Is Best?
Is One Drop-Away Arrow Rest Design Better Than Another?
With drop-away arrow rests there are two basic designs: Buss-cable operated and limb-driven. Both involve springs attached directly to launcher arms. I'll attempt here to detail how each operates, but picking a favorite really comes down to personal preference.
Buss-operated systems (NAP's Apache, for instance) incorpoate springs tensioning launchers continually downward. An activation cord, attached to the downward buss cable, pulls against this spring, lifting the launcher into position at full draw. Upon release the spring pulls launcher from beneath arrow as tension's released from the buss cables. The activation cord is limp at rest, tight at full draw.
Limb-driven designs (i.e. Vapor Trail) incorporate springs continually tensioning the launcher in the upward position, though, a limb-mounted acivation cord continually pulls the launcher into the down position while at rest. During the draw cycle limbs are pulled together, releasing cable tension and allowing the launcher to lift into position. On release the top limb pulls the launcher from beneath arrow as both snap back into position. The activation cord it tight at rest, limp at full draw.
Another buss-activated system is the inertia-triggered rest (QAD's UltraRest, Trophy Ridge's Revolution). They include mechanisms allowing you to cock the launcher in the ready position before shooting, launcher remaining in the upright position after drawing but letting down without shooting. An inertia trigger releases upon release via bow jump, spring tension pulling the launcher away.
The advantages of each are fairly subjective. NAP's Bob Mizek points out that an improperly-adjusted limb-driven design introduces potential fletching contact, and instillation sometimes requires more trail-and-error tinkering for ideal timing. He says buss-mounted systems are easier for the "average" archer to set up and receive good results from. Anchoring activation cords to buss cables requires tightly serving or clamping to assure no slippage, tension adjustments accomplished at the rest.
Vapor Trail's Jarrod Fondie says limb-driven designs offer more accuracy and forgiveness because, firstly, they support the arrow longer before the limb drives the launcher away (faster than spring action), and also the momentary "free-floating" nature of the limb-driven launcher following release is able to better absorb inconsistencies following a rough release or torque, making it more forgiving. The activation cord is attached to the upper limb with any secure knot, adjustment accomplished at the rest.
Popular inertia-trigger rest designs gained loyal converts by providing both total containment of the arrow before/during the shot (even turned upside down) and drop-away clearance after release, even when using large or aggressive fletchings. Though, both the designs I've used as standards above, the Apache and Vapor Trail, offer a high degree of arrow control within launcher-surrounding "cages."
I've used every one of these designs happily and recently. So I guess my final take-way is that I really can't say I've suffered any tuning difficulties with any of these rest designs. I call this a testament to the user-friendly attributes of the lastest drop-away models, and proof that there's more than one way to build a better mouse trap.