With the opening of the 2013 archery deer season less than a month away, my mind has already started its shift from thoughts of big bass to big bucks.
I’ve begun my preparations by shooting as much as possible to become acquainted with the new bow I’ll be hauling into the trees, and determining what arrow works best with my rig.
It was while doing this that I began to think about just how confusing this process can be for many archers, especially since most don’t have a good understanding of their equipment.
Arrow speed has become all the rage in recent years as companies have begun to use this as their primary means of comparison against one another. The truth is advertised speeds have little to do with hunting since no one is ever going to achieve the numbers seen in a magazine ad.
What they can tell you, however, is how efficiently a bow is able to store energy for the shot on a deer or other targeted species.
The archery industry uses a standard method for determining the advertised speeds so that everyone is on a level playing field and consumers aren’t being duped by false claims.
This method was set by the International Bowhunting Organization, better known as the IBO, and calls for companies to determine this speed by using a 30-inch draw, 350-grain arrow and 70-pound draw weight.
Although this puts each manufacturer on a level playing field, the derived speeds this method provides are unrealistic in the field. After all, not all hunters pull a full 70 pounds, only a small percentage has a 30-inch draw, and a 350-grain arrow is the lightest arrow that should ever be fired from such a bow.
For safety’s sake, the guideline for minimum arrow weight on any bow is 5 grains per pound you’re pulling. With that 70-pound draw, 5 times 70 equals 350. A 60-pound draw would mean that a minimum arrow weight would be 300 grains.
Using the smallest arrow possible will result is a faster shooting bow with a flatter trajectory but, as with anything, there’s a trade-off. Light arrows offer little in the way of kinetic energy and “punch” at impact meaning a broadhead that hits off the mark is much more likely to result in a wounded animal.
Guidelines show that a minimum amount of measured kinetic energy for an arrow to adequately penetrate a whitetail deer is about 25 pounds, if an absolutely perfect shot is made right into the animal’s boiler room. A more realistic minimum is around 55 pounds to guarantee a pass through and an ethical kill.
The higher the kinetic energy your bow and arrow combination makes the better. With that in mind, let’s take a look at my bow and several scenarios for arrow selection along with the speeds and “punch” they provide.
For the first time, this year I’ve opted to drop from a bow that’s adjustable from 60 to 70 pounds of draw to one that supposedly tops out at 60. I say supposedly because even that is not a given. With the limbs of my new PSE Dream Season DNA tightened all the way down to provide the maximum poundage, it actually measures out to 64 pounds of draw weight, which is exactly what I shot all of last year on a bow that was adjustable from 60 to 70. Knowing that a bow that’s tightened all the way down creates more efficient energy and can be more accurate, this move made sense for me.
This model of bow has an IBO speed rating of 352 feet per second, but my smaller 28-inch draw and drop in poundage to 64 means that mine can’t get close to that number. That doesn’t mean it can’t put out some blistering speeds, however.
Just consider — if shooting the lightest arrow possible at 320 grains, this set-up still fires an arrow at 327 feet per second. Although that will provide me an extremely flat trajectory that might win me a few archery shoots, the energy left in the arrow at 40 yards is not enough to take a shot on a deer.
A much heavier arrow of 450 grains slows my bow’s speed down to 283 feet per second but provides a whopping 80.05 foot pounds of kinetic energy. That’s a sufficient amount to take down the dangerous African cape buffalo, considered one of the toughest animals for an arrow to penetrate.
This means that the perfect arrow for using this bow on whitetail deer is somewhere in the middle. I’m shooting the new Carbon Express Maxima Red arrows with a shaft length of 25.75 inches plus the nock and a 100-grain broadhead. At 8.11 grains per inch of shaft plus the nock weight of 9.9 grains, a nock collar of 4, three Blazer vanes at 6 grains each, an insert that weighs 11 and the broadhead, my total arrow weight comes to 351.73 grains.
Although this would be considered extremely light on a 70-pound bow with a 30-inch draw, it’s plenty sufficient with my lower poundage of draw and shorter draw length. I’m getting some incredible numbers out of this combination.
With this not quite 352 grains of arrow weight, my DNA is flinging arrows at an impressive – and more than respectable – speed of 316 feet per second. That’s plenty fast for a super flat trajectory that makes accuracy a breeze.
As for the kinetic energy it provides?
Straight out of the bow, I’m getting a huge 78.22 foot pounds. Despite the fact that lighter arrows lose energy faster than heavier ones, the math shows it’s still packing way more than 60 all the way out at 40 yards. When considering that 99 percent of all bow shots here are taken at less than 30 yards and, although opportunities are occasionally provided on our place in Kansas, I don’t intend to shoot beyond 40 yards on an animal, this is the perfect combination for me.
So grab your bow and play around with your arrow selection a bit. Archery calculators for determining your kinetic energy can be found with an Internet search and you might just find something better.
Brad Harvey is a freelance writer in Clover. Visit his website at bradharveyoutdoors.com.