The 'TRUTH' By Bear Archery By Larry Wise
May 2, 2007 - 11:23:00 AM
WHITETAIL UNIVERSITY BOW REPORT
PART 1 of 2
This bow report will be a little different from others you've seen presented in other forums and magazines. Whitetail University is a learning center and, as such, I will do some teaching as I write about what I feel is important for you, the consumer, to know about this particular bow.
I am also a professional shooter with a shooter's value system for rating a bow. I have seven areas of concern when I prepare and shoot any bow: draw stroke, power stroke, set up, draw adjustment, grip design, aiming and grouping. All of them will be presented in this two-part article along with a score for each based on a maximum seven-area total of 100 points.
This rating method and its scale may give you a useful means of evaluating some other bow that has caught your interest. Approaching a new bow with some definite areas of concern and a value attached to them may also help you decide on one bow from among several. Being better informed about bows is a good first step to getting a bow that matches your needs and preferences. And if you're happy, then I'm happy.
The Bear Line of bows are perhaps the best value in the industry.
The graph plotting points for the Bear Truth draw stroke were obtained by first attaching the bowstring to a weight scale. I then attached a rope to the handle and used a winch to draw the bow one-inch at a time, recording the draw weight at each inch of true-draw length (The distance from the grip to the string.) This doesn't take sophisticated equipment as you can see by the photo; just a 2X4 board 6ft. long, a scale and a winch. Most bow reports contain at least one of these force-draw curves because the picture shows you what you feel as you draw the bow. As a shooter I have some important insights about this curve for you to consider.
This simple machine measures the draw stroke that you exert on the bow when you shoot. The end result is a measure of the bows efficiency.
Drawing the Truth from the brace height of 7 inches to 16 inches gives a smooth steady increase in weight. I like this kind of start because it doesn't put an overload your shoulders but you do sacrifice a small amount of stored energy compared to those bows that have a steeper increase on the front slope. The area under this part (area under the curve represents the bow's stored energy) of the curve from 7 to 16 inches is about 67 square graph units. Since each graph square represents four inch-pounds of stored energy, 67 x (4 in-lbs per square) gives us about 268 in-lbs, divide by 12 to get 22.3 ft-lbs of stored energy.
The Method used to determine a force draw curve involves math and graphing. The Bear Truth's Force Draw curve is impressive and reflects sound engineering.
The Truth hits its peak weight when the string is 17 inches form the grip or rest-mount hole and stays there through the 23-inch distance. Through this section of the draw stroke the bow is storing most of its energy, which is indicated by the large area under the force-draw curve. Count the squares in the section between 16 inches and 24 inches and you'll find there are about 8x15 = 120 squares. Again, each square represents four inch-pounds of stored energy and this entire section represents 480 in-lbs or 40 ft-lbs of stored energy.
Drawing the bow further results in a decrease in draw weight as expected. The weight drops from peak to holding weight between 24 inches and 28 ½ inches. This decrease or let-off is about 47#. Divide by the peak weight of 60 and the percent let-off is 78%, which is close to the advertised 80%. Since I don't have sophisticated equipment and the factory does, I have to assume that the let-off really is 80%. The stored energy in this section is about 47 squares, 188 in-lbs or 15.7 ft-lbs.
The draw curve hits the lowest weight or holding weight of 13 # at 28.5 inches of draw from the grip. Remember, this is "True Draw" and that the Archery Manufacturers Organization (AMO) has set its standard draw length to be 1 ¾ " more than the True Draw to incorporate the bow handle geometry from the grip to the back (target side) of the bow. This is done also as a safety measure to insure that archers buy arrows to match their AMO Draw Length; arrows cut to True Draw Length would be too short and would be drawn off the rest causing major hand injuries.
The total stored energy of this bow according to my measuring is 234 graph squares. Multiply 234 x (4 in-lbs per square) to get 936 in-lbs, and then divide by 12 to get 78 ft-lbs of stored energy. That's really good for a 60# peak weight bow that draws as smooth as this one does during the first 17 inches. I'm not a big fan of the steep let-off section on any bow - I like the let-off to begin at about 21 or 22 inches from the riser so its easier on my shoulder (Remember here that I'm a baby boomer and my shoulders have been shooting archery for 52 years).
Rating: 11 out of 15 points.
2) POWER STROKE:
Here's where the bow has to "put up or shut up". How much of the 78 ft-lbs of stored energy can this bow system deliver to the arrow? And, at what price?
The power stroke takes about .015 sec. Yep, it takes less than 2 hundredths of a second for any compound bow to deliver energy to the arrow and send it across the arrow rest. During that time the string moves from 28.5 inches to 7 inches from the riser. The arrow gets kicked in the butt as the string goes from 13# to 60# in just a few thousandths of a second - - - and it actually hits what we're aiming at! When you think about that don't you find it amazing?
The Bear Truth excels in this action. There is so little shock in the handle during and after the power stroke that you have to check if the arrow really got launched. This bow is outstandingly vibration-free during and after the power stroke.
The absence of vibrations is due to several factors: good design, quality manufacturing and integrated vibration dampeners. A large part of this is the parallel limb design that helps disperse energy upward and downward at the end of the power stroke instead of forward toward the target.
The single cam also distributes the forces well between the string and cable at the end of the stroke resulting in little noise. In fact, I let ten different guys shoot this bow at my local club and all ten said the same thing, "Wow, is this ever quiet!" Quiet means that there is no wasted energy causing unnecessary vibrations - there really is something to "tuning" a bow.
Integrating Simms vibration dampeners into the bow system design has a definite advantage. Testing early in the prototype stages enables companies to make the most of a few small dampeners and this bow is exceptional in this regard.
Efficiency is a measure of how well a bow transfers its stored energy to the arrow in the form of kinetic energy. I measured the speed of a 400-grain arrow and found it to be 265 fps at 60# draw weight. The kinetic energy of the arrow is 400x265x265/450240 or 62.4 ft-lbs of energy. Divide this kinetic energy by the stored energy to get 62.4/78 = 80% efficient. That's really high for any machine.
3) SET-UP: INSTALLING THE ACCESSORIES
What I like to do here is to take accessories that I have used with other bows and install them on the new bow. It should be easy since I've already used these items and I should not have to make any special adaptations to get them to work well. In other words, I should be able to use my standard procedure to get a bow ready for the first few shots.
I installed a common simple launcher-style rest with a .012" thick spring steel blade. Then I tied a release loop onto the string so the arrow shaft bottom would be level with the launcher tip and added a peep at my normal height above the nock.
The Sure Lock sight I installed has a 7X Super Scope lens and will give me a good idea about accuracy and how well this bow aims. A quick-release stabilizer attachment will enable me to use my 35" Specialty Archery carbon rod stabilizer. I use these so I can do some long range testing.
All of these items installed with ease with no special adaptations. The only hitch I encountered was with the first shot when the peep was not nearly high enough. This is to be expected with a short axle-to-axle length of 33" since the steeper string angle at the nock requires the peep to be further from the nock in order to be at eye level.
The second part of this two-part article will contain the ratings for the aspects of draw adjustment, grip design, aiming traits and grouping. It will also contain the final total score for this bow and some personal comments. To learn more about the Truth, click the icon below.