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My first serious hunting bow was a Herter's Take-Down recurve. It was a bow that my dad designed and built in the mid seventies. The pull weight was 68 lbs and it shot a 525 grain arrow 170 feet per second (fps). Back then I wasn't concerned about kinetic energy, but the set up generated roughly 33 foot pounds of energy. I was lucky enough to harvest several trophy class animals with this set-up including a P&Y elk taken at 40 yards and a P&Y class moose at 45 yards. Good penetration and good arrow flight were not a problem, however judging distance was critical. 

In 1987, I had a chance at killing my first Bull Moose. It was a huge bull with a massive 63" spread. He was so big it looked as if he were right next to me. I shot him for 25 yards. My arrow dropped low and just tickled his arm pit. In disbelief I stepped off the yardage and found the bull to actually be standing at 30 yards when I shot. At that range my 170 fps arrow dropped roughly 9.4 inches. My arrow had dropped completely out of the vitals and instead of good hit, I had just grazed him.

Today I shoot a Mathews MQ32 at 64 lbs. The bow is shooting a 340 grain arrow 270 fps. My MQ32 is generating 55 foot pounds of energy. If I would have been using my MQ32 in 1987, my 270 fps arrow would have dropped roughly 3 inches. More than likely I would have caught the lower part of both lungs and killed the moose.

You may be asking, how can I be so certain that the moose had a 63" spread. Due to the fact that I grazed the moose, we were able to stay on him and my dad got close enough to make a killing hit about an hour after I hit him. At least I can see this mounted moose whenever I want. It kind of takes the sting out of having him get away completely. Actually, the trip was a big success. On the last day of the hunt, I judged the distance properly and heart shot a 55" bull at 45 yards. 

Today, most set-ups are incredibly fast. You may be thinking, if 270 fps works well, then why not 300 or 320 fps. My answer pertains to the 'Law of Diminishing Returns'. Quite simply, if you keep increasing bow speed, you will reach a point where the excess speed gained, will not proportionately give you what you lost to get it. Here is an example, if your arrow is traveling at 160 fps and you estimate the yardage at 25 yards, but the target is actually at 30 yards, your arrow will drop 10.6 inches below your aiming point.

If you make that same mistake with an arrow traveling 200 fps the arrow will drop 6.4 inches. So by increasing your arrow speed 40 fps you have gained 4.2 inches of trajectory. One could reason then that if we increased our speed from 260 to 300 fps we would again gain 4.2" on trajectory. However, this is not the case. A 260 fps arrow will drop 3.4 inches if you estimate the yardage at 25 yards but the target is actually 30 yards. A 300 fps arrow will drop 2.4 inches under the same circumstances. By increasing your arrow speed 40 fps, you only have gained 1" of trajectory, not the 4.2 inches you would expect.

As with everything, there are trade offs involved. In order to gain 40 fps, using the same bow, you would have to drop to a lighter arrow. In doing this you will compromise efficiency. As you go to lighter and lighter arrows, you approach more of a dry fire situation which puts tremendous strain on both the shooter and the equipment. The bow becomes louder and a greater amount of energy is transferred back into the bow, limbs, cables, string and accessories including the sight. In addition, the bow will vibrate more making it both uncomfortable and more critical to shoot. When it comes to shooting fixed blade broadheads, I have found that anything over 260 fps becomes critical. Some of my pro staff shooters can get smaller 1 1/8" dia. broadheads, like our Rocky Mountain Titanium 100's or Premier 75's to fly well up to 280 fps. Anything over 280 fps for the average bowhunter, in my estimation, is too critical to take into the field after game.

If you feel you have to shoot faster than 280 fps, you most likely consider yourself to be an above average shooter. If you are having trouble getting your conventional broadheads to group well, you may want to consider either backing off a bit or using expandable broadheads. However, as with all things, even here there are some disadvantages to using expandable broadheads. (See my earlier article of the advantages and disadvantages of expandable broadheads.)

If you feel you have to shoot faster than 280 fps, you most likely consider yourself to be an above average shooter. If you are having trouble getting your conventional broadheads to group well, you may want to consider either backing off a bit or using expandable broadheads. However, as with all things, even here there are some disadvantages to using expandable broadheads. (See my earlier article of the advantages and disadvantages of expandable broadheads.)

If you have any question, comments, concerns, or suggestions for future "Cutting Edge" columns, E-mail me at cuttingedge@bowhunting.net.