While thumbing through traditional

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1 AS /31/05 12:40 PM Page 81 The Carbon Challenge Part One By Brian Sorrells While thumbing through traditional archery catalogs a while back, I noticed that they all carried one or two brands of carbon arrows in addition to the standard wood and aluminum offerings. Interesting, considering that the consensus of traditional archers everywhere used to be that carbon arrows are decidedly not traditional enough to shoot from a stickbow. Could it be that there are enough traditional archers out there shooting carbon arrows to make it worthwhile for traditional archery suppliers to carry an assortment of soda straws? Being an open-minded individual, I think that if it s acceptable for a longbow or recurve to contain carbon and fiberglass laminations, then it s okay to shoot an arrow made of carbon. I have used carbon shafts in the past as stump shooting ammo, mostly because I had a few on hand and didn t really mind losing a few. These were the older style, very skinny with an outsert on the point end and constructed of carbon filaments layered over an aluminum core. I didn t care for these arrows much because every time the shaft took a glancing blow, the aluminum core would bend ruining the entire arrow. I was surprised by the durability and toughness of the carbon exterior however, and thought that if someone would invent an all-carbon arrow with a larger outside diameter, they would really have something. Another discouraging rumor during the early days of the carbon arrow was that if you shot an animal with one and the shaft broke off, carbon fibers would become embedded in the meat and be ingested by the hunter. In fact, some of the first carbon shafts bore a warning that read something like: Use caution when consuming meat from an animal shot with a carbon arrow. The three test shafts were, left to right, the Heritage 350 by Carbon Express; the Grizzlystik from Alaska Bowhunting Supply; and the Gold Tip XT. Carbon arrow manufacturers continued with technical advances and soon came out with an all-carbon arrow that was larger in diameter and broke cleanly, keeping meat contamination to a minimum. Companies like Gold Tip offered an all-carbon shaft featuring a weight system that allowed archers to make shafts as heavy as needed. But the attitude of the traditional community remained unchanged for the most part and carbon never seemed to gain much acceptance until lately. Considering myself somewhat a rebel, I decided to give carbon a chance and set out to obtain representative samples of what s on the market. I wanted to use well-known brands and find out if they would meet the requirements of traditional archers and bowhunters. After looking at a lot of advertisements, the three shafts I chose were the Gold Tip graphite XT, the Carbon Express Heritage 350, and the newest carbon arrow to hit the market - the Grizzlystik from Alaska Bowhunting Supply. The Carbon Express shaft came equipped with a nock that inserted securely into the end of the shaft, but without a point insert. The Gold Tip XT came with the same type of nock, and also a nock adapter that allowed the use of adapter weights. A point insert compatible with adapter weights accompanied the Gold Tip, along with enough of these weights to add about 250 grains to the total weight of the shaft. The Grizzlystik came with a nock adapter and a brass point insert that also accepted adapter weights. Another Traditional Bowhunter Aug/Sep

2 AS /31/05 12:41 PM Page 82 Weights and adapters allow easy tuning as well as providing a heavier shaft for bowhunting. interesting note was that the Grizzlystik was tapered over the entire length of the shaft rather than just the first few inches. All test arrows were of the correct spine weight to shoot from my test bow, a 60 Red Fox longbow from Fox Archery that pulled 65 pounds at my 27 inch draw length. I chose this as my test bow because it has features common to modern stickbows and I shoot it comfortably. As stated earlier, I wanted to know if carbon arrows would fulfill the needs of the die-hard traditional archer. Trying to take all aspects of traditional archery into consideration, I came up with some characteristics that a shaft should have in order to make a good traditional arrow: Usability, Tunability and Durability. Usability- Do carbon shafts come in spine weights to match any traditional bow, from the 35-pound minimum most states have for legal hunting weight all the way up to 100- pounds for those who hunt Cape Buffalo with their traditional bows? Can old or damaged feathers be replaced without major surgery? I determined that carbon arrows do come in spine groups from 35 pounds on up to about 95 pounds, most in fifteenpound groups, i.e pounds. Of course spine weight is affected by a combination of arrow length and point weight, so I m convinced that anyone willing to put forth a little effort tuning the arrow to shoot properly from the bow can find a carbon shaft that will work. Tunability- I believe that all arrows should be bare shaft tuned to shoot from the intended bow. If the shaft flies straight without fletching, once feathers are added it will fly even better and carry a broadhead without a problem. Bare shaft tuning consists of starting out with a shaft that s a few inches too long, a nock but no feathers, and a field point with a weight that matches the hunting broadhead to be used. Start out with the nocking point on the bowstring about 1/2 inch above the shelf, and begin shooting the arrow into a bag target. If the nock ends up to the left of the spot where the arrow sticks in the target (for right-handed shooters), the arrow needs more spine, so cut about a quarter inch off the point end and shoot again. If the nock end ends up to the right of where the arrow is sticking in the target, then the arrow already has too much spine. Either use a much heavier point or get another shaft with less spine. Simply continue shooting and shortening until the bare shaft sticks fairly straight in the target in the left and right plane. (Always use a high speed shaft cutter on carbon arrows to get a clean cut that won t fray!) Then gradually move the nocking point down until the shaft sticks fairly straight into the target in both planes. This method is simple, and it works with wood and 82

3 AS /31/05 12:41 PM Page 83 aluminum (although you may end up with an arrow that s longer than you want when the shaft is properly tuned when using wood or aluminum). Here s the really cool part about carbon arrows: a considerable amount of weight can be added to the point end, drastically affecting arrow spine. This weight system works by using a point insert that s fully threaded and allows weights to be securely screwed into the backside of the insert. These inserts and weights are available to fit virtually every carbon arrow on the market. (Gold Tip offers its own adapter weight system.) This system accomplishes two goals at once. First, it allows you to start the bare shaft tuning process with a shaft that s already the correct length for you. Instead of trimming off the end of the shaft, you simply add additional weight until you reach the correct spine. Second, this allows for a variety of field point and broadhead configurations. One of the things I disliked most about aluminum arrows was that I could never find a screw-in type broadhead in a style I liked that was heavy enough. I would end up gluing a traditional broadhead onto an adapter to get the weight I wanted, and I never could get all six broadheads from one package to spin true. Now I can shoot those light 125 or 130 grain screw-in broadheads, still get enough weight up front to achieve good arrow flight, and have a broadhead that spins true! Some of you may be shaking your heads and thinking that my Front of Center balance must be way out of kilter. I ve never been able to get my FOC within the recommended 15% anyway, but my arrows fly like darts so I don t care. Durability- Would carbon arrows stand up to the rigors of stump shooting (a favorite pastime) and still maintain integrity? After all, compound shooters are the target consumer group for most carbon arrow manufacturers and I don t know a single compound shooter who does any stump shooting. Would a carbon arrow stand up to the demands of varied climates from deep-freeze cold to desert levels of heat and jungle-type humidity? Would the finish stand up to repeated use with foam targets, or would it degrade as the anodized finish on my favorite aluminum shafts did? Once I received my test arrows, I decided to put them through a little torture test to find how they stood up before I shot them. While straightness is always important, all three of my test arrows were rated at +/-.003% straightness. Like most bowhunters, I have little scientific background so I just rolled them across a flat surface. No problem; they were all straight. But what if they were subjected to different environmental factors like cold, heat and humidity? I don t recommend re-creating the following tests on your own carbon shafts because I doubt the manufacturers would honor any warranty or be liable for any damage incurred! As a matter of fact, if any of them are reading this, they are probably cringing and screaming, You re not supposed to do that! But I wanted to see how tough these shafts were, so I attempted to recreate realistic environmental exposure factors that an arrow might experience in a hunting situation. The first study, what I ll call the humidity test, wasn t all that radical. Traditional Bowhunter Aug/Sep

4 AS /31/05 12:41 PM Page 84 A properly tuned bare shaft will stick reasonably straight in the target, even without fletching. I simply soaked the raw shafts in a tub of water for eight hours, allowed them to dry, and then checked for any warping. There was none. The next step, a little higher on the radical scale, would check how well the shafts handled extreme cold, as on those late season bowhunts we sometimes subject ourselves to in order to fill that huge hole in the freezer. I simply placed the shafts in the freezer for six hours, then removed them and gave them a good flexing (something each manufacturer recommends before each shot). I was pleased not to hear any cracking noises, and the shafts passed the table top test without any signs of warping. My last and most radical test was to check how carbon shafts withstand relatively high levels of ambient heat. Carbon arrows are made with a combination of carbon fiber or filaments and high strength epoxy resins, so I wondered how heat would affect the composite materials in the shaft. I simply placed the raw shafts inside my truck and parked it in the sun with the windows up on a hot day. (Hey, who hasn t done something similar accidentally?) I placed a thermometer in the truck to measure the temperature. After five hours, the temperature inside the truck was around 88 degrees, so I left them inside a couple of more hours to be sure. After seven hours, I removed the arrows and gave them a good flexing and twisting to check the integrity of the materials. Once again, I detected no problems and the shafts remained straight. Now it was time to get down to some serious testing. I wanted to start with each shaft cut to the correct length 84

5 AS /31/05 12:41 PM Page 85 The big Zwickey Delta flew well with each of the test shafts. Be sure to test your own broadhead flight when switching to carbon! instead of having to shorten the shaft after each shot. I planned to add weight to the front end to achieve proper spine. I had each shaft cut to 29 inches and laid out my weight adapters to prepare for bare shaft tuning. Arrow weight is (or should be) of great concern to us as bowhunters. I prefer my arrows to weigh at least 8 to 10 grains per pound of bow weight. My longbow draws 65 pounds, which means that my arrows need to weigh from 520 grains to 650 grains. The Gold Tip XT shaft and the Carbon Express Heritage 350 shaft each weighed 238 grains as a raw shaft cut to 29 inches. To achieve my required weight, I would need to add at least 282 grains. The Grizzlystik weighs around 15 grains per inch for the Alaskan model. That means that my Grizzlystik as a raw 29-inch shaft weighs about 435 grains, so I only needed to add about 85 grains to make it work. But I m a fanatic about bare shaft tuning so I would have to wait and see how much weight I needed to add to tune the arrow before I could figure out how much my total weight would be for each shaft. I use a field point/broadhead that weighs around 175 grains, so there was some additional weight already. I then completed the bare shaft tuning process for each of the shafts, all of which tuned easily by the simple addition of weight adapters to the point end. (I used Bohning s PowerBond adhesive instead of hot melt glue to avoid using direct heat.) Once bare shaft tuning was complete, I ended up with the following total weights for each arrow: *Carbon Express Heritage 350: 544 grains, including field point. *Gold Tip XT: 557 grains, including field point. *Grizzlystik: 620 grains, including field point. I felt encouraged by the finished weight of these arrows because I was afraid those shafts would never come close to my personal requirements. However, they made weight with no problems! I fletched these shafts with five-inch shield cut feathers and proceeded to the range for accuracy testing. You ll notice that not once have I mentioned arrow speed. Here s why: I DON T CARE HOW FAST IT GOES! Arrow speed, while it does contribute to kinetic energy, is much less important than accuracy. If your arrow goes 200 feet per second but corkscrews and flies like a wounded duck, you can t hit what you re shooting at and everything else is irrelevant. I shot each brand of arrow numerous times to see if I needed to make any adjustments to my sight picture and to check for consistent arrow flight. I then shot each arrow as a group. There was a little difference in the points of impact for each shaft when shot as a group, possibly because of the difference in arrow weights, but more than likely it was just me. Consistent accuracy with individual arrows (as far as my limited talent allowed) was excellent out to my personal effective range of 25 yards. For flight-testing purposes, I used a Zwickey Delta 4-blade broadhead (glued onto an adapter) for each shaft. The total weight was the same (175 grains) as the field point weight. I shot each shaft individually out to a range of 25 yards, and each shaft flew well. For a broadhead target, I used a section of high density styrofoam covered with a heavy layer of very tough rubber. This block was once part of the orange flotation ring on a U.S. Coast Guard cutter, and is very consistent in mass and composition. I checked penetration on each shaft. The Grizzlystik penetrated deepest (14 inches), followed by the Gold Tip XT at 12 1/2 inches and the Carbon Express at 10 inches. The differences in penetration were probably caused by a combination of arrow weight and arrow finish. The Grizzlystik was heaviest and had a smooth epoxy finish. The Gold Tip XT was next heaviest, with a smooth hardwood finish. The Carbon Express shaft was the lightest of the three and had a somewhat rough finish comparable to a stained cedar shaft with no clear coat. In the next issue, we ll cover my stump shooting adventures, discuss all our findings, and learn a little more about the Grizzlystik. See you then! Brian Sorrells is a fulltime police officer and part time outdoor writer living in Bedford, IN. His book Beginner s Guide to Traditional Archery was recently released by Stackpole Press. Traditional Bowhunter Aug/Sep