Shooting targets out to 100 yards with a crossbow is a lot of fun, but that’s not as good of an idea in hunting situations. A 400-grain bolt fired from a crossbow traveling at 300 fps retains enough kinetic energy at 80 yards to cleanly harvest deer-sized game. Still, putting that arrow in the kill zone at that distance is a big challenge.
By design and because of the optics (scopes) used, crossbows can be shot much farther accurately than vertical bows can. But an arrow (bolt) has a dramatic drop in trajectory, especially at distances past about 40 yards. Granted, crosshairs on scopes designed for crossbows can be set to and sighted in at exact yardages. A crosshair set for say, 85 yards will likely result in a miss or a wounded animal if the actual distance to the animal is 91 yards or 79 yards.
Big-game animals seldom stand broadside long enough for the range to be accurately measured and then the shot executed. In the real world, that buck or bull or wild hog is much more apt to take a step in one direction or another. That move increases or decreases the actual distance and angle of shot placement.
So just how far should a crossbow hunter shoot a game animal? That is a loaded question that requires an understanding of trajectory. Only part of that answer can be determined by shooting in the field with the bolt/broadhead you’ll use when hunting. Broadheads fly differently and there is no trajectory chart to tell where you’ll actually impact a target with the broadhead you are shooting.
Many of us old-time hunters use the term “hunter’s zero” to determine the yardage to zero our weapons. Most crossbow scopes are graduated in increments of 10 yards. In truth, there is very little drop from 10 yards out to about 30 yards. That’s especially so with today’s very fast crossbows that zip arrows along at 350 or 400 fps. I like to zero the top crosshair at 25 yards, which equates to the “hunters zero” (from point-blank out to about 35 or 40 yards) for deer hunting.
A deer’s vitals are contained in a 10- or 12-inch vertical zone. A bolt aimed at the center of the vitals with that 25-yard crosshair will be well within the vitals out to 40 yards. It may land an inch high if shot at 10 yards and possibly three or four inches low if shot at 40 yards but will be well within the kill zone.
If you are hunting elk, this kill zone expands to about 16 inches vertically. A crossbow bolt leaving the rail at say, 350 fps travels about 175 feet (or 58 yards) in the half second before impact. A second might not seem like much time. In a real-world hunting situation, it is plenty of time for a tightly wired Whitetail or wild hog to quarter its body enough for the shot to result in a wounded animal rather than a clean harvest. Reduce that near-60-yard shot down to 35 yards and the time it takes the arrow to impact the animal is reduced by an appreciable amount. This is exactly why I avoid those longer shots at game.
However, there are other ethical considerations to be made before taking shots at game animals that are over 40 yards away. Crossbows are not nearly as quiet as longbows. The sound of the crossbow being discharged reaches the animal well before the arrow traveling 350 fps does. An alert animal can move before the arrow reaches them, resulting in a wounded animal. At longer distances, there is more likelihood that the shooter may not see small obstructions in the path of the arrow, such as small branches or bushes or trees. Even grass or weed stems can deflect the arrow and potentially set the stage for a wounded animal or a difficult recovery. A slight breeze will alter the flight of the arrow and must be compensated for if accuracy is to be achieved at longer distances. I recommend a maximum of 40 yards for most shooters. The longest shot I’ve made at game with an arrow is 35 yards. There is just too much room for error when longer shots are taken.
Trajectory charts can be very helpful and will give you a good idea of where the bolt will be at various yardages. However, nothing takes the place of actually shooting to determine the exact trajectory of the bolt and broadhead you’ll use on your hunt. The increments of 10 yards in elevation are standard for many crossbow scopes, but some of my extensive test shooting could be avoided if using the “hunters zero” method above.
In truth, it is a great confidence builder to shoot targets from 10 yards out to one’s maximum hunting yardage. In hunting situations, I have found it very helpful to have only one crosshair to consider. A great deal happens in a very short time when a deer, antelope or wild hog finally offers that perfect broadside shot. The last thing I want to be doing during that critical period is counting down the scope’s crosshairs to determine the one that best suits the distance I ranged. Trust me, it’s much easier to use that top crosshair on your x-bow scope, place it in the center of the kill zone and begin your trigger squeeze knowing that the broadhead will fall a reasonable distance within the animal’s vitals.
The Energy, Too
While trajectory is probably the most crucial factor when sighting in a hunting crossbow, kinetic energy also comes into play. Most experts suggest a minimum of 27 foot-pounds to about 40 foot-pounds is needed to cleanly harvest deer-size game.
Rather than getting bogged down in charts giving foot-pounds of energy with different arrow weights and speeds, a simple comparison gives the crossbow shooter a good idea of what to expect from different arrow speeds and weights. A 400-grain bolt fired at 300 fps develops about 76 fp (foot-pounds) at 10 yards. At 40 yards, it’s still packing about 66 fp. A bolt traveling at 400 fps develops about 135 fp of energy at 10 yards and retains about 120 fp out to 40 yards. Most of today’s crossbows shoot over 250 fps and the majority shoot 300 to 400 fps. All come out of the box with power that is more than ample to cleanly harvest game out to 40 yards and farther. It’s pretty easy to determine that arrow drop (trajectory) is far more important than kinetic energy when determining the maximum ethical distance to shoot game.
It’s not my intent to dissuade anyone from shooting game at distances of greater than 40 yards with a crossbow. Personally, this relatively close-in type of shooting matches my skills. After about 60 years of hunting big game, I disdain long tracking jobs or worse, losing game because I attempted to shoot an animal at a distance that wasn’t comfortable. Occasionally, we all pull a bad shot, regardless of the range. But the goal as ethical hunters is to practice enough to feel confident when we set our sights on an animal. The one crosshair zero and taking only reasonably close shots gives me the confidence and results I need when that game animal presents a high-percentage shot opportunity.
My best advice is to shoot your crossbow often and at various yardages with the bolt/broadhead you will use to hunt. Use shooting sticks when you can, just like when you shoot your hunting rifles. Determine what your maximum comfortable yardage is and don’t attempt to push your limits. When determining that yardage, keep this in mind: It doesn’t take much movement of a targeted animal at distances past 40 yards for things to go wrong. Your goal is meat on the game pole, not a frantic search for a wounded animal that you might never recover!