Field Evaluation - BowTech® Guardian By Keith Dunlap
Apr 2, 2007 - 10:09:08 AM
BowTech has made their mark on the archery industry over the past few years with bows that are not only fast but also quiet and virtually shock free. The introduction of their revolutionary new Center Pivot riser, which supports the split limbs at their center causing them to flex and pivot differently from other bows, keeps BowTech on the cutting edge of design and technology in the archery world.
In this field evaluation, we will take a close look at the BowTech "Guardian", a bow that BowTech claims is intended to "provide the ultimate bowhunting experience combining the values of Center Pivot and CenterTrac binary systems that provide superior comfort and performance". I will attempt to validate this statement as I put the Guardian to the test.
The appearance of the new Guardian takes some getting used to for those who resist change, but once you shoot one you quickly realize that this new design works.
Guardian Basics Riser: The camo risers are finished using a hydrographic film dipping process. The riser on the Guardian is a deflex riser made from forged and fully machined 6061T6 aluminum. Reflex and deflex are terms used to explain the geometry of a riser. A deflex riser bow will have a higher brace height than a reflex riser bow which generally means it is a more forgiving bow. A reflex riser bow has a shorter brace height which usually translates into a less forgiving bow than a deflex riser bow. Reflex/deflex is measured by the position of the throat of the grip in terms of its location from a line drawn from each of the pocket pivot points on the handle. If the throat of the grip is in front of the pivot point line it is considered deflex, if it is behind the pivot point line it is considered reflex. Reflexed risers tend to be more susceptible to hand torque. The new BowTech Center Pivot design features a conventional riser that lashes the pockets up at the ends of the riser. With the Center Pivot design, the limbs are positioned behind the grip, making the Guardian's riser a deflexed riser. The result is that the limb tips move less mass weight, less limb movement, and improved efficiency from a long stable riser that balances well for its overall length…this equates to less hand torque during the shot.
BowTech%u2019s Center Pivot design puts the throat of the grip in front of the limbs.
Cams: The Guardian incorporates the CenterTrac Binary Cam system. With the original Binary Cam system, both harnesses are anchored on the opposite cam so the system cannot go out of balance…so timing adjustment is not necessary. For 2007, BowTech redesigned the Binary Cam so that the harnesses attach to the axle on both sides of the string groove. The CenterTrac Binary Cam has the same advantages as the original Binary Cam, but this added feature also eliminates cam lean and balances the force on the tips of the limbs improving torque during the shot. The result is increased efficiency and truer arrow flight.
Limbs/Limb Pockets/Limb Rocker: The Guardian is equipped with two 12" split limbs. Rather than a traditional limb pocket, the Guardian uses an axle tie that ties the limb together, but does not really act as a pocket for the limb since the Center Pivot arm is where the limb begins to bend when drawing the bow. The axle ties are located at the front of the riser where the poundage is adjusted. The limb rocker is located in the center of the limb where the Center Pivot technology is utilized. This rocker is machined from 6061T6 aluminum and allows the limb to pivot.
Silencing System: The Guardian comes adequately equipped with a VibraBlock String silencing system which includes: 4 String Silencers, 2 Vibrablocks & 1 Cable Muffler. BowTech calls this a "Hush Kit", and it is produced from a proprietary rubber-like compound. It should be noted that it takes more than a "Hush Kit" to make a bow silent when shot. The BowTech Guardian is manufactured for silent, vibration-free shooting. It is the primarily the design of this bow and its components that makes it a quiet bow. I found no reason to add extra silencing components to this bow.
My evaluation began with a thorough visual examination of the BowTech Guardian for any workmanship issues or defects. The bow was visually flawless with one minor exception; the camo had been rubbed off on two of the corners of the lower limb. The cams moved freely when pressure was removed from the strings and cables. All parts fit together perfectly, nothing was loose, and the bow was mechanically sound. I would expect this type of quality workmanship from BowTech.
My initial Set-Up.
The only items added to the bow for testing were a N.A.P. QuikTune 3000™ arrowrest, and I removed the brass knock that came installed on the string and replaced it with a D-loop. I chose 350-grain Carbon Express Maxima 350 arrows for my evaluation. The bow was paper tuned and ready to shoot.
Comfort of shooting bow…when shooting the Guardian, it became clear to me that BowTech has developed a product that really backs up their claim of a quiet shot with superior comfort. Starting with the grip design, the Guardian was very comfortable to grip using my straight-wristed style of gripping a bow. The bow grips rested well in my hand. The addition of the new modular grip system that is comprised of two extremely thin side plates makes this bow extremely comfortable to hold for longer periods of time, in addition to aiding those who tend to torque their grip during the shot.
I shot sets of 30 arrows each day for a week to evaluate overall comfort, draw cycle, shock, vibration and torque. I also shot a three other bows I had in stock for comparative purposes throughout the evaluation.
Starting with overall comfort, I must say that the Guardian is as impressive a compound bow as I have seen in quite a while. It was a pleasure to shoot this bow from start to finish. I found that the draw cycle was very smooth and consistent throughout the draw…no major inclines or declines in the draw curve. Often bows that generate the kind speed that the Guardian generates will have a difficult draw curve, but not so with the Guardian. The draw cycle is smooth and this bow generates plenty of speed.
My next area of focus was to concentrate on the amount of shock and/or vibration felt during each shot. This one is tough to measure other than feel or the amount of "jump" felt upon release of the string. You should really compare the bow you are evaluating to other bows on the market to really feel the difference. A visit to the local archery shop should provide ample comparison. After shooting the Guardian for a week, compared with the few bows in my shop plus a trip to the local archery shop, I can tell you that the Guardian really does back up its claim to be superior in comfort and performance. Minimal, if any, "jump" was felt when I released the string, and the Guardian was by far the smoothest shooting bow in the many I shot during this evaluation.
Noise level…the proper method to evaluate noise level would be to use a decibel meter capable of measuring low noise levels. I don't have access to one, so in order to evaluate the noise level of this bow, I had a few family members and my hunting partner close their eyes and listen next to me while I shot various bows in our indoor target range. I shot one arrow from each of four bows in their "out-of-the-box" condition, including the Guardian, and recorded the reactions of each person in succession. I repeated this test several times until I was able to average the results. The Guardian was voted the quietest bow that I shot according to each person helping me with this test. The BowTech Tribute ran a close second. To reiterate, I evaluated this bow as it arrived from BowTech with only an NAP QuikTune 3000 Rest and a D-loop added. I found the extremely low noise level during the shot to be one of the best I've experienced. No need to add more silencers to the Guardian "out-of-the-box".
A 'Birth Certificate' comes with every BowTech bow.
Speed…the Guardian I evaluated had a measured peak draw weight of 72.9 lbs and a measured draw length of 29.1 inches. I adjusted the draw weight to exactly 70 lbs to replicate the IBO requirement for the speed evaluation. Speed was measured on a Pro Chrono chronograph. I measured 18 shots and averaged the results. The average speed of the 350-grain Carbon Express Maxima arrows as they flew from the Guardian was 306 fps. Just for kicks, I then measured 18 shots with one of my 376-grain CE Maxima hunting arrows. The speed dropped to 296 fps with the heavier arrow. Under the I.B.O. (International Bowhunter's Organization) standard, a bow should have a draw weight of 70 lbs, a draw length of 30 inches, and the arrow should have a grain weight of 350 (5 grains of arrow weight per pound of bow weight). In my opinion, the measured Guardian speed of 306 fps with the 350-grain arrow and the shorter draw length of 29.1 inches is within range of the advertised IBO speed of 320-328 fps if the bow had a 30-inch draw length.
Maneuverability…I evaluated maneuverability by shooting the Guardian from various positions in a ground blind and from a tree stand. I took several shots seated, kneeling, and standing from within the ground blind and from a tree stand. I must admit that I am used to the short axle-to-axle height of my BowTech Tribute at 31.5". The Guardian is 2.25" longer axle-to-axle than my Tribute. This caused only minor adjustments to various positions while shooting the Guardian. The Guardian is very maneuverable in real hunting situations; I just had to remember that I had a slightly longer bow in my hand while making those maneuvers.
The Guardian is a superb bow from axle to axle. I found this bow to be one of the most comfortable bows I have experienced thus far. The hand shock and overall vibration during the shot is minimal to non-existent, and the Guardian is one of the quietest bows of the 2007 lineup. As you would expect from BowTech, the speed of this bow is excellent. An added feature, which I really like, is that the new Center Pivot bows from BowTech allow you to adjust draw weight, work on strings, and add peep sights without the need for a bow press. Simply back out the limb bolts 5 turns at a time for each limb until the limb bolts are showing three threads visible in the viewing hole of the riser. String tension is minimal allowing you to work on the bow as needed. Do NOT back the limb bolts out beyond the 3 visible threads of the limb bolts in the viewing hold on the riser as this could damage your bow.
Guardian with Limb Bolt backed out.
This rating chart is intended to help you investigate a single bow by reviewing its key features, and also compare it to other models you may be interested in. A rating system of 1 through 10, in ½ point increments, will be used with 1 being the lowest and 10 the highest or best.
Following is a list of the bow properties that will be covered and their definitions.
Grip: This item will be rated on its "feel" and shape in regard to the effect it has on torque and the overall enjoyment of shooting.
Maneuverability: This rating is self-explanatory and will be determined through various field tests, including ground blinds and treestands. Mass weight will also be a factor.
Speed: The rating for this category will be based on the design and intended purpose of the bow. For example, if the bow being tested is a youth model, it will not be expected to spit arrows out at 300+ fps.
Quality/Workmanship: Again, self-explanatory. This item will be based on attention to detail in the areas of machining, finish, and general mechanics.
Shock and Vibration: Ratings will be based on the amount of "jump" felt upon release.
Noise Level: Noise will be rated without any noise dampening devices installed. This will allow the test to be based solely on the bow's out-of-the-box performance. This category is closely related to that of the shock and vibration category.
Draw Cycle "feel": The perceived smoothness of the draw is the focus of this rating.
Shootability: Many factors come into play here, including axle-to-axle length, brace height, and eccentrics.
Advantage: What makes this bow special? Why choose this bow over another?
Category - Rating - Comments:
Grip - 10
Maneuverability - 9.0
Speed - 10
Quality/Workmanship - 9.5
Shock/Vibration - 10
Noise Level - 9.5
Draw Cycle "feel" - 9.5
Shootability - 9.5
Advantage - 9.5
Average Score - 9.61 out of possible 10
Total Score - Out 86.5 of possible 90
Draw weights: 50 through 70 pounds peak (72.9 lbs. as tested)
Draw Lengths: 25-30.5 inches, modular, ½ inch increments (29.1 inches as tested)
Axle-to-axle length: 33.75 inches
Brace Height: 7 1/8 inches
Mass Weight: 4.2 lbs
Let-off - Adjustable from 65% to 80% (80% as tested)
Eccentrics: CeterTrac Binary Cam System
Advertised IBO speed: 320-328 fps
Advertised Kinetic Energy: 81.6 fpe
Available finish: Mossy Oak Obsession, Realtree Hardwoods HD, Realtree Hardwoods Green HD, Mossy Oak Brush
Cable: 22-strand 452X
String: 22-strand 452X
Grip: 2-piece rosewood side plates are stock, options include laminated one piece or a heated grip that is currently under development
Riser: Deflex Riser 6061 T6 Aluminum
Limbs: 12" solid split limbs
Cable guard: Carbon - Straight Carbon-epoxy cable rod
Silencing System: VibraBlock string silencing system including 4 string silencers, 2 VibraBlocks, and 1 cable muffler
Warranty: Limited lifetime to original owner
For More Information On This And Other BowTech Products Visit: BowTech