LETS TAKE UP PRIMITIVE SHOOTIN'
See our staff writer's Bio in the Jan/Feb 07 issue of the North American Frontiersmen's "Smoke Signals".
Don’t think for a moment that any old arrow will shoot well out of any old bow. Shooting the wrong arrow won’t do the job; it will not shoot consistently.
Every bow has a specific arrow that it just loves and that is why we spend so much time finding the ultimate shaft just as we do bullets for our rifles and pistols.
In our modern age the best shafts I have found are Port Orford cedar, especially compressed cedar if you can find it (unlikely). There are other compressed wood shafts as well, but as usual the cost is well over the top. My advice in this area is to stay with the equipment that is available and shooting rules and just have fun.
To purchase arrows I suggest that you buy them by the dozen. In this way you will know that you at least have a matching set. Almost without exception if you buy through mail-order you are going to find that only about nine out of twelve shafts will be straight. If you learn to straighten shafts you will still discover that at least one of the dozen will become a stick, good for doweling, perhaps. Bill Cunningham insists that the best source he has found for purchasing shafts is Valley Traditional Archery (VTA) which can be found on line, but if you want to order through a real person they are located in Silt, Colorado, phone or FAX 970-876-0170. Bill claims that in years of doing business with them he has had only one shaft that turned into a stick and that one they replaced free of charge and no arguments. And he buys lots of shafts.
The stiffness of the arrow shaft is called "arrow spine." It is the measured deflection, in inches, of the shaft when depressed by a weight at its center. An arrow shaft of the proper spine should not wobble when it leaves the bow—provided that the bow is properly set up and tuned (yes, even primitive bows need tuning). Something else you should understand about the spine of an arrow is that changing the length of an arrow will also change its spine. Making an arrow an inch shorter or longer will change it enough that it may not fly well out of your bow so when ordering you should get them cut to your draw length so the spine will be will not be for a longer arrow. You also want the proper spine so that your arrows are uniform in weight. They must all match for consistent shooting. The slightest variation will cause the arrows to fly differently from one another and cause you to grumble about not being able to "print" well on the target or to hit game where it counts. You should either purchase or make your hunting and practice arrows exactly the same. If you don’t know the shaft weight in grains you want when ordering shafts, if you give the weight of your bow to the supplier they will sell you arrow shafts spined to that weight bow unless you specify otherwise (not wise unless you are experimenting). There is no better way to prove an arrow’s worth than by shooting it. Have someone stand behind you, in a slightly elevated position, and watch your arrows fly as you shoot. They should be able to determine just what the arrow is doing, such as porpoiseing or staggering, etc. Bill can tell much about the arrow’s performance by doing a neat little thing with shooting an arrow through a sheet of paper and then studying the holes made by the fletching. A characteristic of arrows is that those that are too light for you bow tend to hit to the right of where you aim, and those that are too heavily spined go left.
Hunting arrows will differ from target arrows in that they are heavier shafts, have a longer fletching, and shoot a bladed broadhead that also could be heavier. I always try and shoot a 120 grain field tip and the same weight broadhead. My target tips are of 70 grains weight. Here I’m looking for distance. Bill tends to shoot field tips of either 70 grains (for distance) or 100 grains (to match the weight broadheads he makes and uses. The tip of your arrow should be seven to ten percent heavier than the shaft. This is important for good arrow balance and good arrow flight.
Being that most of my shooting is geared toward hunting, I shoot this equipment every chance I get. I’ll shoot field tips at home made targets and I’ll shoot broadheads at sandbanks at various distances. Keep in mind that the smaller the target the tighter your groups will be. And keep in mind that unfiltered sandbanks often contain rocks.
My 55 pound hunting bow shoots a 28 inch shaft (I will, however, add an extra inch for broadhead clearance). So I’m really shooting a 29 inch arrow with a spine rating of either 55 to 60 or 60 to 65 pounds. The fletching is five inches long and five eighths high at the tail for stability and twist. My broadheads and field tips are 120 grains. If I should get an arrow that flies consistently off the bull, I set it aside. It helps to number your arrows. Some shooting matches require you to number your shafts for shooting animal targets. You generally shoot three arrows and only the first arrow is your score.
Bill Cunningham has a neat system where he uses different colored fletching for different sets of arrows or else crests them in specific colors. Green is for this weight bow, brown is for that weight, and yellow is for distance, etc. Also on your arrows, mark the spine weight and arrow length. This is good information to have with you and besides, it makes us look like we know what we are doing.
You should make yourself a measuring arrow. Take a full size shaft of 31 inches or better and put a nock on it.. Lay it along side a measuring stick and mark all the inches from inside the nock forward. Put clear lacquer or varnish over it so the writing doesn’t rub off. This is a great tool to have, especially if you have growing children around that shoot. Place this arrow on the bow and have the person pull to their full and comfortable draw length. Pinch the shaft between your fingers right against the back of the bow (the part of the bow farthest away from you). Remove the arrow or have the person slowly let it down (never dry fire a bow). Now, provided that they always come to the same nocking point, you have that person’s exact draw length. It is amazing how many people, when asked their draw length will either have no idea or else will tell you it is something way beyond what it actually turns out to be. In order to get the correctly spined shafts you have to know the right draw length! Just because a person is six foot six doesn’t mean they will have an extra long draw length, nor will a person of five foot six necessarily have a short draw length. Try measuring each person you are with after you’ve asked what their draw length is and you will often be surprised at the variances between what they, and you, think it is.
Now let’s take a moment to look at arrow weight of a twenty eight inch arrow fitted with a broadhead for arrow balance. The center of the arrow is fourteen inches from inside the nock to the tip of the broadhead. The balance point measures two and three quarters inches toward the nose. To find out how nose heavy your arrow is, take the difference, in this case 2 ¾ inches, and divide it by the full length of the arrow. The formula thus is 2¾ ¸ 28 = 9.6%. Your hunting arrow should be about 7 to 10% heavier in the tip. Arrows are more accurate when they are 7 7o 10% nose heavy. Correct arrow balance is necessary for good arrow flight.
Another factor to consider is kinetic energy, which is energy that is released from the bow and transferred to the arrow when shot. Take a bow of say, 40 pounds for deer and 50 or better for elk. Kinetic energy times the arrow weight in grains, times the square of its speed in feet per second (that is, multiply speed times itself) then divide this figure by 450240. This is energy, in foot pounds, that the arrow has when shot. The formula then is: arrow speed (fps) X arrow speed (fps) X arrow weight in grains over 450240. A chronograph will give you arrow speed. Say the speed reading is 190 fps (good luck!) And the weight is 600 grains. The arrow will have 48.1 fp of kinetic energy. So 190 X 190 X 600 ¸ 450240 = 48.1 fp.
Now that you have that information you can astound your friends (and perhaps some professional bowyers) with this fascinating data: If a bow stores 50 foot pounds of energy and the arrow has 35 fp when shot, the bow efficiency is 70% (35/50 = 70, or 70% with that arrow. This is called relative efficiency. This is arrow kinetic energy divided by its peak draw weight. Example: Relative bow efficiency = kinetic energy foot pounds. Draw weight at release (pounds) 80% (48.1 fps ¸ 60 pounds = 80.1% relative efficiency which equals a very efficient bow and arrow combination, and that’s a keeper if you can draw it comfortably! Heavier arrows resist air current less and arrive down range with more energy than a light arrow but light and heavy arrows have their trade offs as you will discover if you shoot often enough and think about what is happening with each shot.
I hope I got all that right. You can now see how serious this sport can become—especially if you start making your own arrows.
Until the next issue, shoot, shoot, shoot. Wax, wax, wax.
period shootin' pertaining to those than went before us.
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