How can weight-forward arrow designs — tapered or built-in weight forward — benefit your bowhunting pursuits?
Traditional bowhunters have been shooting tapered wood arrows for ages. The obvious question is why? An easy answer would be that since traditional arrows are shot directly off a hard (if padded) shelf, a nock end smaller in diameter than the front provides improved arrow clearance around the riser. This appears intuitively correct, and many traditional archers no doubt have chosen tapered shafts for this reason alone.
But like many archery-related subjects, a simple explanation is only a portion of the overall equation. This becomes more pronounced in the age of modern compounds, and especially drop- away arrow rests with guaranteed arrow clearance — even with arrows holding rigid “cartridge” fletchings.
F.O.C., or Front of Center, is the percentile difference between the mathematical center and center of gravity (balance point, point installed), compared to an arrow’s total length.
An easier way of stating this is how far forward an arrow’s balance point is situated from its mathematical center. Why is this important? Without proper F.O.C. — without sufficient forward weight — you create a situation where the nock end of the arrow is attempting to overtake the front while in flight. In other words; unstable flight.
Eight to 9 percent F.O.C. is typically offered as minimal for reliable field-point and streamlined mechanical broadhead flight, 10 to 12 percent for fixed-blade heads. Find this number by determining the mathematical center of your hunting shaft (nock throat to cut-off point) and marking it, then its balance point (point installed) on a sharp object and marking that. Then divide the distance between these points by overall arrow length (nock throat to cut-off point), and move the decimal point two spaces right to receive a percentage.
As important as this is, there are other positive factors involved. Higher F.O.C. also lends an arrow a higher degree of forgiveness — an arrow that wants to stay its course following a bad release or after encountering light deflections. It will also, all other factors remaining equal, penetrate deeper.
F.O.C. is bumped by increasing the weight of the point (from 100 to 125/145 grains) or insert (brass instead of aluminum, for instance) — something most bowhunters seem allergic to. Or, you can choose an arrow with built-in weight forward, sticking to the broadheads you already own and love and maintaining every foot per second of arrow speed possible.
Built-in weight forward means tapered shafts, as already mentioned, but also special carbon-construction processes seamlessly melding heavier material/tighter weaves up front with lighter materials at the rear.
This is straightforward stuff, but there are other forces at work in the typical weight-forward arrow design. This involves dynamic spine. A typical straight-walled arrow may flex anywhere along its entire length during launch. Not really a major problem, because fletchings are there to quickly introduce order to this chaos.
Where weight-forward shafts really shine is broadhead accuracy. This is especially true with standard-diameter, fixed-blade heads. The smaller rear end of a tapered, or engineered “softer” rear section of a dynamic spine shaft allows the rear to absorb the parallax or acceleration oscillations of launch, while the broadhead is held on a stiffer front end that flexes or oscillates less or not at all. This keeps the leading broadhead parallel to the direction of travel and less apt to grab air and alter an arrow’s path. And since arrow flex/oscillations are isolated to specific portions of the shaft, each arrow is launched more consistently, leading to improved overall accuracy.
Tapered shafts, like boat-tail rifle bullets, also exhibit superior long-range aerodynamics. This advantage isn’t likely to reveal itself when limited to the intimate ranges at which most Eastern whitetails are shot, but can spell flatter trajectory for the bowhunter who takes 40- to 50-yard shots at Southwest Coues’ whitetails.
So as you can see, there really is something to all the hype surrounding weight-forward arrow designs; including higher F.O.C.s and its positive influence on flight characteristics, increased forgiveness and penetration, better broadhead accuracy — and yes, even improved arrow clearance off the shelf while shooting traditional bows.
— Patrick Meitin is an accomplished bowhunter and outdoor writer from Idaho.