Looking at wood arrows online for the first time can be pretty daunting for a newcomer. What are tapers, spine, diameter and which ones do I need? It’s not as simple as cutting them to length and matching the poundage to your bow. For the sake of simplicity I’m going to go through the process based on the 3riversarchery site but most suppliers are the same.

Spine

Arrow spine is the measure of stiffness of an arrow shaft. It’s usually determined by a jig where the shaft rests on two points that are 26″ apart with a 2 lb. weight in the middle. The amount of deflection is written down and compared to spine chart for that particular material. Carbon is written as a number 300, 400, 500, 600, etc with the lower number being stiffer/ less deflection. Aluminums are different in that they have two sets of numbers, 1816, 1916, 2116, 2514, etc. The first two digits are the diameter of the shaft and the second two are the thickness of the walls. Stiffness isn’t measured for these so you just have to look at a chart. Wood arrows are measured in pounds but has little relation to the draw weight of a bow. They usually come in increments of 5 or 6 such as 40-45#, 45-50#, 60-65#. So if you order a dozen 40-45# arrows you’ll get a variety of shafts that may be 40, 41, 42, 43, 44, or 45#. Wood arrows aren’t as consistent as other materials but they can be tuned easier than most.

Arrow Chart

Tapers, Points, and Nocks

With wood arrows the points and nocks have to be glued on rather than using inserts and screws. Tapers are cut into the ends of the shaft to hold them. The arrow supplier will cut and mount points for a fee but it pays off to own a taper tool and the pencil sharpener types aren’t very expensive.

The best glue to use when mounting points is hot-melt because it lets you change points if you need a better weight.

Points

Points come in weights measured in grains similar to ammunition. 125 gr. is the standard for hunting weights but lighter ones are beneficial for target shooting. The points also have to match the diameter of the arrow shaft and usually come in 5/16″, 11/32″ and 23/64″

Shaft Diameter

Woods are sold in 3 major diameters which are 5/16″, 11/32″ and 23/64″. Why are they such obscure measurements? I don’t know, but I have a theory it’s similar to Fender hardware not being standard so Joe can’t just get his parts from the hardware store for a quarter of the price… The diameter really doesn’t matter all that much except that it may be difficult to find 80# shafts in 5/16″. Narrower diameters generally have a lower spine and weigh less than bigger diameters.

Fletchings

People get bent out of shape when choosing fletchings but there isn’t much to it. The only goal of the fletchings are to create drag and keep the back of the arrow in the back during flight. Bigger fletchings create more drag – slows arrow faster – minimizes effects of poorly spined arrows. Helical means the feathers are spiraled around the shaft and usually stabilize the arrow faster than straight feathers. Plastic vanes are lower maintenance but can’t be shot off the shelf or the hand.

Dynamic Spine

Dynamic spine is the sum of all the parts of an arrow to match a bow. It starts with the static spine of the arrow and factors in length, point weight, diameter, etc. Longer arrows lower the dynamic spine, high point weight lowers the dynamic spine. You can’t just cut arrows to an arbitrary length and call it good because you’ll end up with arrows that are too stiff and don’t shoot straight. Knowing this is useful for tuning arrows on your own so you can start with the charts I linked above or you can use this calculator by Stu Miller. If you don’t know the weight of the shafts assume that port orford cedar is 300-400 grains, or 10 grains per inch.

Here are some examples I ran through the calculator:

Generic Selfbow/Longbow 40# @ 28″ cut .25″ from center – Arrows are 40#, 10 GPI, 11/32″, 30″, 125gr point, 3×5″ feathers. Total arrow weight is 440 gr and 11 grains per pound.

Samick Sage 45# @ 28″ B-50 string, center cut – Arrows are 60#, 11 GPI, 11/32″, 30″, 125gr point, 3×5″ feathers. Total arrow weight is 470 gr. and 10.4 grains per pound.

Modern Bear Grizzly 50# @ 28″ Fast Flight string – Arrows are 80#, 12 GPI, 23/64″, 30″, 125gr point, 3×5″ feathers. Total arrow weight is 500 gr. 10 grains per pound.

Generic Horsebow 30# @ 28″ Fast Flight string, no arrow shelf – Arrows are 30#, 9GPI, 5/16″, 30″, 100 gr point, 3×5″ feathers. Arrow weight is 380 gr and 12.7 grains per pound.

All of these were based on the limits of the “3 Rivers Hunters” but the 30# horsebow was just at the lower limits of those arrows. Part of it was that there wasn’t a shelf cut in so it needed a very low spined arrow, and I couldn’t add much length or weight to the front of the arrow because i was already pushing the weight at 12 grains per pound. All of these bows need vastly different arrows to shoot straight so you can’t interchange one for another.