Coping With Cant, Wind and Rifles That Don’t Stay Still:
A Few Pointers for Greater Accuracy
by Wayne van Zwoll
A combination of little things working together sometimes puts your bullet where you don’t expect it.
If you do things in a natural sort of way, you hold a rifle with the sights on top and the trigger on the bottom, just as you drive a car with the shiny side up. But unlike automobiles, rifles aren’t connected to the ground. Rifles can be tipped as easily as you tip your hand. They can be fired at a tilt or even upside down. While most shooters keep the sights on top, many do not. Those who tip their rifles are said to be canting.
“A cant isn’t bad,” a shooting coach told me long ago, “so long as you do it the same each time.” Doing it the same each time presupposes that you know you’re doing it in the first place. Riflemen who don’t think about cant either tip the rifle at pretty much the same angle out of habit, or they allow the angle of the sights to change slightly with each shot.
It’s pretty easy to spot a cant if you’re coaching, just as it’s easy to see the tilt of a truck loaded too heavily on one side if you’re driving behind it. In the truck’s cab, you might not be able to tell; and when you’re looking through the sights you often can’t tell either.
A shooter used to canting his rifle will likely mount a scope so the crosswire is tilted off the vertical axis of the rifle. You’ve probably thrown a friend’s rifle to your shoulder and had to consciously rotate the stock so the vertical wire would appear to be straight up and down.
Discussions with friends about canting can get animated in a hurry. About the only way to settle them, short of spiking the stew with cigar tobacco at elk camp, is to lay the rifle in a rest or across sandbags on a bench and square up the stock by nudging the butt so a plumb line or carpenter’s level shows it to be vertical. Now, without moving the rifle, look into the scope. The crosswires should appear to be vertical and horizontal. If they are not, you simply loosen the scope rings and twist the tube.
That is, unless you want to leave the reticle as is.
A canted reticle will not cause a miss. In fact, you can rotate the scope so the crosswire looks like an “X” and use it as effectively as before. A small disadvantage is that you won’t have a vertical wire to help you hold off for wind deflection or show you the line of bullet drop at long range. You won’t have a horizontal wire to help you lead running animals.
A canted rifle, however, is another story. Regardless of how the reticle appears, if the rifle is tipped, you’ll have problems hitting beyond zero range because the bullet path is not going to fall along the vertical wire or directly below the intersection. If your sightline is directly over the bore, a long shot requires you only to hold high. If your sightline is forced by a canted rifle to the side of a vertical plane through the bore, you’ll not only have to hold high, but to one side.
Here’s the reason: Given that your scope is mounted directly above the bore, your line of sight crosses the bullet path twice. The first crossing happens at about 35 yards; the second is at zero range—say 200 yards. If the rifle is rotated so the scope falls to the side of the barrel, the sightline will cross only once, because gravity sucks the bullet straight down, while the line of sight has a horizontal component. Whether the scope is on top of the rifle or a bit to the side, the line of sight will converge with the bullet path, slice through it, then angle away. If the scope is on top of the rifle, gravity pulls the bullet in an arc back into and through the straight line of sight. If the scope is not on top, the bullet path still dips below the horizontal plane of the sightline; but when this happens the trajectory is well to the side of where you’re looking.
How much practical difference will canting make? Not much. A cant that escapes your notice won’t cause a noticeable shift in bullet impact at normal hunting ranges. As the targets get smaller and the range longer, and as you impose stricter accuracy standards, cant starts to matter.
When I was on the Michigan State University rifle team, I marveled at a colleague who shot very well but used a cant that would have spilled coffee. Standing, he looked straight ahead through sights that fell into his natural line of vision when he rotated the rifle on his shoulder. The adjustable butt let him do that without changing the contact angle of the butt hook. So his rifle tilted in toward him. Not only the line of sight but the rifle’s center of gravity fell closer to the centerline of his torso. From a mechanical perspective, this made perfect sense. I tried shooting that way and found it darned near impossible.
In traditional bull’s-eye rifle competition, targets are very small and the rifles supremely accurate, so shooters must correct for cant. (Some globe sights for target rifles have tiny bubble levels that show you the slightest cant at a glance, and similar devices are now available for scopes.) On the other hand, my teammate on the smallbore squad didn’t have to worry about horizontal angles because his shooting was done up close at one precisely measured distance. It is easy to accommodate cant at a single distance. You simply move the sights to put the bullets where you look. Forget about how sightline and trajectory converge and what they do beyond the target. It doesn’t matter.
We elk hunters don’t shoot at just one distance, however, or with adjustable stocks. So although small degrees of cant seldom affect our performance on game, it’s a good idea to shoot with the sights squarely on top of the rifle. Cant is just one more thing to worry about, one more distraction, a small but thorny threat to the self-confidence that can help us shoot well. It’s easy to see if you have a cant. Simply loosen your scope rings and line up the vertical wire with the butt of your rifle. Now tighten the rings. Throw the rifle to your shoulder with your eyes closed. Open them. The wire should appear vertical. If it does not, you’re tipping the rifle. Practice holding it with the sights at 12 o’clock, where they belong.
Sometimes shooters slip a cant into their shooting routine without knowing it. They mount the scope carelessly and subconsciously adjust their hold on the rifle to correct for a reticle that’s tilted. A culprit here is the ubiquitous Weaver Tip-Off scope ring. This inexpensive ring has been around a long time—and for good reason. It’s strong and lightweight. But because the top half hooks the base on one side and its two screws take up all the slack on the opposite side, tightening a Tip-Off ring can rotate the scope tube down toward the screws. If they’re installed on the right-hand side, you put a clockwise tilt into your reticle as you cinch them up. You may have aligned the reticle perfectly with the butt before installing the top part of the rings, but now the crosswire is tipped! Solution: back off on the screws and twist the scope counterclockwise about as far as you think it moved. Tighten the screws again and check the reticle.
Now, canting isn’t the only way you can complicate your aim at long range. When I was growing up, side-mounted scopes were common. With them, you could affix a scope to a top-ejecting Model 94 or 71 Winchester, so you could use your iron sights and a scope without removing the scope. If it holds the scope off the vertical axis of the bolt, a side mount introduces the same sighting error you get with a cant. Side mounts that put the scope over the receiver are best. A Remington 870 shotgun in my rack wears a side mount, but the scope lies almost directly over the center of the bore. Side mounts installed before rifles were routinely drilled for scopes made hash of collector-quality rifles. Many Winchester Model 54s and 70s, and untold numbers of lever-action carbines, were assaulted with drills in the decades of innocence following World War II. After it dawned on shooters that a pre-war hunting rifle might someday be worth more than $100, and that holes in the receiver were like rust pockets on Duesenbergs, drilling stopped.
Top mounts centered above the bore can give you problems with sight angles too, if the bases are extra high. It’s easy to see this in exaggeration. Picture a scope with ring bases 3-feet high. If you adjusted that scope to put its bullets on point of aim at 35 yards, you couldn’t expect it to give you a 200-yard zero. The reason: Directing the line of sight to intersect bullet trajectory at 35 steps puts the two paths at steep angles to each other. The entering and exiting angles are naturally the same. Your sightline now diverges quickly from the bullet’s trajectory, diving under it in a straight but steeply descending path. The bullet will come down to meet it, courtesy of gravity. But that won’t happen for some distance.
I once watched an elk hunter miss a stunning bull from prone, with a rest. The distance was perhaps 300 yards. He asked me where to hold, and I suggested high behind the shoulder, assuming his rifle was zeroed at 200. I checked it later, shooting to ranges of 400 yards. It was zeroed at 330. The shooter had fired it previously only at 100 yards, and someone had told him that bullets striking 3 inches high at 100 would be dead on at 200. They neglected to point out that the super-high rings necessary to get his astronomy-size scope clear of the barrel put the line of sight at a steep angle to the trajectory. Result: more distance between the crossings.
But truly, errors caused by cant and steep sight angles pale beside those caused by rifles that don’t stay still. Holding a rifle steady and executing a shot smoothly are still our most important tasks when the time comes to shoot an elk. We need help to keep that rifle under control.
A lot of hunters are discovering the value of a bipod. A bipod puts the rifle in contact with the ground, replacing slippery joints, pulsing arteries and quivering muscles with a couple of dispassionate steel pegs that don’t move. At all. What could be better? Well, the best bipod is one that allows some movement at the attachment point. The Harris bipod that I favor is cleverly designed to allow the forend to roll slightly. When you have to take a shot from a place that is not perfectly level, you can quickly extend the legs to roughly the proper length, then make up for induced cant by tilting the rifle to vertical as you aim.
Shooting sticks are an alternative to the bipod. Buffalo hunters used crossed shooting sticks to steady their heavy rifles. Lighter, stronger fiberglass versions are available from Stoney Point Products. The firm’s Steady Stix and taller Safari Stix collapse for carry in a belt sheath. From the sit or kneeling, plant the stick legs well forward and pull the intersection toward you as you push into it with the rifle. The rifle shoves the legs more firmly into the ground as your hand (or a tight binding of some sort) keeps the sticks at a constant angle to each other.
A monopod offers some support, but not as much as crossed sticks because it allows left-right wobble. Mainly, it keeps your left arm from getting tired. It is easier to carry and quicker to deploy than a bipod or crossed sticks, however, and is considerable help when you’re winded and the muzzle wants to dip and soar at each breath.
In my opinion, the best shooting brace is a sling—not a carrying strap, but a 1-inch or 1¼-inch leather shooting sling with an adjustable loop that snugs around your left arm above the triceps. The loop hauls the rifle back toward you, transferring rifle weight from your left forearm to your left shoulder while snugging the butt into your right shoulder. If you simply wrap a strap around your arm, you tug the buttstock forward because the strap is as tight behind your triceps as in front. Also, the pull on the butt is to the side, inducing a cant.
To my mind, Brownell’s “Latigo” sling is the best commercial shooting sling. It has little hardware—one button and a ring—so is quiet and lightweight. You can adjust overall length with a couple of tugs. A series of opposing holes give you almost limitless loop adjustment. The Whelen-style sling is my second choice. It is less readily adjustable for overall length but offers the same advantages when you shoot. Any nylon sling is bad business because under tension it can slip.
Though a sling won’t steady your rifle as effectively as a bipod, it is quicker to use and better for shooting on steep or uneven terrain. It adds no extra weight or bulk to the rifle and can be used when prone, sitting and kneeling. From prone you should be able (with practice) to keep all your shots inside 3 minutes of angle. That means killing shots on elk to 400 yards. From the sit, some shooters do almost as well. Kneeling typically puts a 3- to 9-o’clock wobble into the reticle, but on a still day, a 4-minute kneeling group is certainly within reach. Recently, shooting prone with Winchester 140-grain Ballistic Silvertip factory loads in a 7mm STW Model 70, I kept 10 bullets inside a 6-inch cluster at 200 yards. Sitting and kneeling, I opened the group to 9 inches. Hardly stellar performance, but adequate for shooting elk to 300 steps.
Of course, if you find a natural rest, use it! Often I use a sling with a rest. Nobody will take you to task for an ugly position if the bullet lands in the middle. When you have the choice, pick a horizontal rest over a vertical support. Your rifle will bounce away from a rest before the bullet leaves the muzzle, and that bounce affects your shot. The bounce most like the bounce you got zeroing is upward off a horizontal rest. Never rest the barrel; and always pad the forend with something soft to minimize harsh vibrations.
When you rest your rifle against a supple young tree, try grasping the tree instead of the forend, steadying the forend with index finger and thumb. The rifle should rest across the web of your hand. Press forward on the tree to load it with tension. That tension will eliminate some of the wobble. Whatever rest you use, crouch as low as you can, to keep your center of gravity close to the ground. The lower you get, the less you’ll sway, if the position is comfortable. You’ll also recover faster from recoil and be less conspicuous.
Competitive shooters know that if they get out of position between shots, they’ll throw a lot of bullets wild. Reason: The rifle yields to the pulsing, twitching, quivering platform holding it. Even subtle changes in that platform cause changes in point of impact because they affect your ability to keep the barrel pointed in the right direction as you fire. It’s crucial that hand, shoulder and cheek pressure be consistent. These are all components of position. If they vary, so will the rifle’s movement at the shot. Your bullets will land in different places.
Offhand is a tough position in part because you feel an absence of position. That is, you feel compelled to make your muscles direct the shot. If you muscle the rifle toward the target, without enabling it to find its natural point of aim, you’ll be fighting it during the shot and while the bullet is moving up the barrel. You’ll miss. Shift your entire body so the rifle points toward the target naturally, minding foot position and letting your skeletal structure take over as much as possible. A solid stance is the foundation of good accuracy.
After you zero your rifle from a hard rest, take it off the bench and shoot it offhand, then sitting, with a tight sling. Firing 10 shots from each position, you may see three different group centers. The rest allows the rifle to recoil straight back and up. Offhand, you can’t provide that solid bottom support; also, you’re unsteady, so you may have a tendency to horse the trigger. A lower group will result. Sitting and slinged up tight, you inhibit the rifle’s bounce skyward, and you tug the barrel to the side at the same time. It’s a good idea to study targets shot from various positions, so you know how position is likely to affect your next shot at an elk.
No matter how accurate your rifle or how solid your position, you won’t hit center if you ignore wind. Wind speed and angle both affect bullet path. Imagine being in the center of a huge clock face, with 12 o’clock straight out in front and 6 o’clock directly behind. Forget about wind coming from between 11 and 1 o’clock, and between 5 and 7 o’clock. Wind that angles toward you from 10 or 2, or flanks you from 4 or 8, must be reckoned with if you’re shooting beyond point-blank range and the breeze is clocking over 15 mph. A “full-value” wind—from 3 or 9 o’clock—gives you the most trouble because, like gravity acting on a bullet fired horizontally, it is pushing at right angles to the bullet path.
A bullet’s vulnerability to wind depends on bullet velocity and ballistic coefficient, or “C”—a numerical sum of shape, weight and diameter. Bullets of similar C show about the same wind drift. For example, consider a 130-grain .270 bullet, a 140-grain 7mm, a 165-grain .308 and a 210-grain .338. If they’re all Partition spitzers from Nosler, with essentially the same nose shape, they’ll be close in C value— from about .390 to .440. Launched at a common 3000 fps, all these bullets will drift about 6 inches at 200 yards in a 20-mph crosswind. Drop C to .289 with a 150-grain .308 protected-point bullet, and drift goes up 50 percent, to 9 inches. A wind far from the muzzle moves a bullet more than does the same wind close up, because downrange the bullet is traveling slower. On the other hand, wind at the firing point can change flight angle of the bullet, whose altered course then multiplies the wind’s effect over distance.
Incidentally, rifling twist can put a vertical component into wind drift. With an ordinary right-hand twist, you’ll get a lift to 10 o’clock from a 3-o’clock breeze, while a wind from the left will drive a bullet down to 4 o’clock. You probably won’t notice such subtleties shooting at elk, but a combination of little things working together sometimes puts your bullet where you don’t expect it. Knowing how cant, body position and wind affect point of impact can help you hit elk.
Wayne van Zwoll has published a dozen books, more than 1,500 articles and 3,000 photos about guns, ammo, optics and hunting. He has been a guide and logger, holds a Ph.D. in wildlife policy from Utah State University and was one of the Elk Foundation’s first field directors. His Bugle column, inaugurated in 1986, is our longest running department.