Should I set My Bow’s Weight at Max
Posted on July 6, 2011
Q: Joe, I really enjoy your magazine. I have heard the same comment made many times over the years. I am wondering if itâ€™s based on facts, studies, opinion or an old wivesâ€™ tale? It goes something like, â€œA bow performs better if the bowâ€™s weight is set at its max,â€ or â€œIf you shoot at 63 pounds, itâ€™s better to have a 50-to-60-pound bow and set it at its max (60 pounds) than to have a 60-to-70-pound bow set at 63 pounds.â€ I am not sure what â€œperforms betterâ€ means.
If you shoot lots of arrows, is it better for the bow to be shot at its max? Wouldnâ€™t this be putting maximum pressure on the bow on each and every shot over and over? Thanks for your input.
J.B., via e-mail
A: This is true from what I understand. Efficiency (speed) is higher, since brace height is usually lower (a tad) with the limbs cranked down more and the strings/harnesses are tighter, creating more launching thump. This information is based on what engineers have told me, as well as from my own experience.
However, Iâ€™ve shot plenty of 60-to-70-pound bows in the low 60s with exceptional accuracy and quietness. As long as the bow features a rotating limb pocket (nowadays, most do), accuracy wonâ€™t be a problem, since the limb butt always stays in precise alignment with the riser and wonâ€™t vibrate excessively. Yes, you give up a bit of speed, but sometimes, you gain a bit of brace height by doing it this way.
â€œMax pressure?â€ All of todayâ€™s bows are made with pretty strong materials, so pressure should never decay a bowâ€™s integrity. I donâ€™t see this as an issue.â€”Joe Bell
Q: Hi, Joe. My local dealer sells Darton bows, and the owner says he only carries them because they are the only ones worth a hoot. I know that bows are just like vehicles: All of them are pretty good, so it comes down to personal preference. But, besides half a dozen magazine ads, I havenâ€™t seen anyone â€œpushingâ€ them. According to the storeowner, Darton holds almost all archery patents for cams. I just nodded my head in agreement, but I was thinking that he was trying to sell me a bow. I love my Hoyt (itâ€™s my third one) and donâ€™t really care either way. I just want to know if Iâ€™m being snowed.
Joshua, via e-mail
A: Darton makes a great bow, but â€œfeelâ€ is so important. Hoytâ€™s feel may be the perfect thing for you, as it is for many. For example, the grip is better than a lot out there, in my opinion.
A dealer pushing one type/brand of bow is too suspicious for me. Rex Darlington (Dartonâ€™s owner) is a phenomenal and highly regarded engineer, but just because a company uses a certain idea/patent/concept from someone else, it doesnâ€™t mean it is a â€œbad seed,â€ by no means. In other words, mechanical concepts are one thing, but ergonomic bow feel is another (i.e. how it aims, balances, feels in the hand, etc.). Most â€œbetter ergonomicsâ€ come from years and years of actual hunting/target time and hands-on experience in the fieldâ€”something Hoyt has proven to have, time and again.
I always tell guys to handle and shoot a lot of bows and then form their own opinions, based on personal feel and draw length. Hope this helps.â€”Joe Bell
Diamond vs. Bowtech
Q: Joe, I just started reading your magazine two months ago and really enjoy it. Several years back, I had a serious back injury but can still do some archery hunting. Iâ€™m looking for a new bow that will be used for antelope. I need a smooth-drawing bow that breaks over fairly easy. I can still pull 60 pounds and want the most â€œpopâ€ I can get. I have considered the Diamond Outlaw and Bowtech Air Raid SC. Which do you feel is the better bow, and why? Do you have other thoughts? Thanks so much.
Jack, via e-mail
A: The draw force curve for the Air Raid SC is less aggressive; however, a 53-pound Outlaw will shoot the same speed as a 60-pound Air Raid SC. This being the case, I would recommend a 50-pound Outlaw, because the draw cycle will be easier to manage. The holding weight would be less, as well. Additionally, the mass weight is less on the Outlawâ€”which can be a factor for injured shooters. Hope that helps.â€”Craig Yehle, senior engineer, Bowtech Archery
Q: Joe, Iâ€™m about to buy a Mathews Z7 Xtreme. I understand that you like the AAE and Limb Driver rests. What about the Mathews Downforce rest? Iâ€™ve read that it does not put any pressure tension on the cable. Is this correct? It looks as if it connects to the cable, but perhaps it operates differently. What are your thoughts? Could you list the advantages and disadvantages to the rests youâ€™ve recommended? Thanks.
C.L., via e-mail
A: The Downforce is an excellent rest, but I prefer the AAE and Limb Driver, which are extremely forgiving and accurate. Both use a flexible launcher arm (AAEâ€™s is more flexible), which dampens arrow takeoff for greater accuracy. I also believe the limb-activated models may stay up longer and drop quicker, but Iâ€™m not sure. I just know Iâ€™ve used all of them and prefer the forgiveness of these models.
The AAE is especially nice. It uses a secure limb-sandwich (with easy-adjust screw) and a coated steel-braid cord that wonâ€™t stretch and is impervious to weather. It all makes for a pretty bulletproof setup. Hope that helps. The Xtreme is a nice bow.â€”Joe Bell
Downrange Arrow Energy
Hi Joe. Great mag! I have four different bowhunting magazine subscriptions, and I honestly feel that I learn more reading yours than I do in the other three combined. Hereâ€™s my question: I am in the market for new arrows. Iâ€™m looking at Easton Axis 340s and Easton Flatline 340s. Here are the respective performance numbers: Axis 428-grain arrow at 279 fps=74 foot-pounds/kinetic energy; Flatline 381-grain arrow at 305 fps=73 foot-pounds/kinetic energy. These specs are straight out of the bow. Arrows are cut at 29.5 inches and shot from a Hoyt Maxxis 35 with 30-inch draw at 65 pounds.
Can you tell me how much kinetic energy each arrow has at 20, 30, 40, 50, 60, and 70 yards without shooting through a chronograph at each distance? I hunt turkey, deer and bear in Massachusetts but plan on elk hunting soon out West. I donâ€™t want to have to change my setup. Thank you.
J.N., via e-mail
A: Thanks for the compliments and for writing in. Refer to this online calculator and find out your arrowâ€™s energy values: http://peteward.com/ballistic.calc.htm.
Also, hereâ€™s a note about momentum from Darin Cooper, Hoytâ€™s ex-senior engineer. It is an excerpt from my book (Technical Bowhunting). Itâ€™s something to consider when measuring the advantages and disadvantages of arrow weight. Hope it helps.â€”Joe Bell
â€œI definitely think archers shooting less than 400 grains on an elk or even mule deer and northern whitetails are asking for trouble regardless of arrow velocity,â€ says Cooper. â€œIâ€™ve done some engineering calculations that indicate how critical mass is to maximizing penetration. My calculations show that 50 grains of arrow weight is equivalent to shooting a 10-pound heavier bowâ€¦ In other words, a 500-grain arrow shot from a 60-pound bow will achieve roughly the same penetration as a 70-pound bow with a 450-grain arrow. The key is momentum and not kinetic energy.â€
â€œWe got handed down kinetic energy as a measurement from the firearms industryâ€”theyâ€™re concerned about knock-down power, kinetic shockwaves, and bullet expansion for a projectile thatâ€™s designed to stop in the animal,â€ says Cooper. Hydraulic shock and energy transfer is highly velocity dependent. â€œOur killing efficiency is determined by how far the object will penetrate and cut tissue. The laws of physics dictate that when comparing two identically shaped objects in motion with equivalent momentum, one being heavier and the other faster, the heavier object will always travel farther (out-penetrate) because it has derived more of its momentum from mass.â€ Momentum = (mass x velocity) Â· 225,218. The units of momentum are (pounds-force x second)