Compact riflescopes like this Leupold FX-II Ultralight 2.5x20 mm are ideal for lever guns used in the timber or for dangerous-game rifles. (Photo by Richard Mann)
May 29, 2024
By Richard Mann
Shooting at longer distances has become popular, and many hunters like the idea of having added reach. This preference has spawned a new breed of precision rifles light enough to carry into the backcountry. It’s also produced a new strain of variable-power riflescopes that help make getting hits at longer distances easier. However, most of these riflescopes are much heavier than conventional designs. Consider that the top three deer hunting riflescopes recently named in an online list had an average weight of 27 ounces. But are scopes this heavy necessary for most hunters?
In his 1970 book, “The Hunting Rifle,” celebrated gunwriter Jack O’Connor wrote, “I rather doubt if more power than 4X is needed for any big game hunting under any conditions.” To an extent, Jack was right, but I’m more inclined to suggest 1X of magnification for every 100 feet of actual shot distance. My experiences hunting big game all over the world have shown me that sometimes 4X doesn’t provide the adequate resolution necessary for an ethical shot. However, that doesn’t mean you need to go out and get a 2-pound riflescope in order to effectively hunt big game.
WEIGHT MATTERS Riflescope weight matters in several ways. The first is the ability of the mounting system to withstand the shock of recoil. The heavier the riflescope, the more stress that’s applied to the mounts during recoil. Hard-kicking lightweight rifles amplify this. A friend stopped by the other day with his lightweight .338. He’d just mounted a heavy, long-range wonder-scope, and after about a dozen shots, everything went haywire. It wasn’t the mounts, though; the scope gave out.
Another issue is that a heavy riflescope negatively affects rifle balance. The balance point of a rifle should be—ideally—right at the front action screw. This puts most of the rifle’s weight between your hands. Riflescopes are mounted behind the front action screw and this—especially with a riflescope that weighs nearly 2 pounds—will make your rifle butt heavy. A butt-heavy rifle will handle well, but it’s harder to hold steady on target when shooting offhand.
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The main contributors to riflescope weight are tube diameter, objective size, number of lenses and the size of external adjustments. Depending on how and where you hunt, bigger versions of these things might not be important.
Lightweight scopes with lower magnification ranges fit most hunting needs, and they’re perfect for inline muzzleloaders. (Photo by Richard Mann) Tube Diameter A riflescope with a 30 mm tube is often thought to be stronger. This is not necessarily true. If the walls of the scope tube are of the same thickness, the smaller 1-inch tube is just as stiff. Adjustment range is an advantage of a 30 mm tube. Comparing Leupold’ s 1-inch and 30 mm 3.5-10x40 mm VX-3HD riflescopes , the one with the 30 mm tube has about 36 percent more adjustment. Still, the adjustment range in the 1-inch riflescope is enough to compensate for trajectory well past 500 yards with most high-velocity rifle cartridges.
Adjustment range used to be much more important before rifles and mounting systems became so precise. On most modern rifles, it’s rare to have to adjust more than about 5 MOA from reticle center to zero a riflescope when quality mounts are used.
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Objective Size The diameter of the objective is where a lot of weight is added to a riflescope. A 50 mm objective lens will generally weigh about 60 percent more than a 40 mm objective lens. In addition to the increased weight, the larger objective also requires the riflescope to be mounted higher, and this requires higher and heavier rings. Some hunters believe objective diameter helps with light transmission, but in truth, magnification and lens quality matter more. The main advantage of a large objective lens is a larger exit pupil. But at 9X, the exit pupil difference between a 40 mm and 50 mm riflescope is only about 1 mm.
Lens Quantity Light is diminished every time it passes through a lens, and the more lenses a riflescope has, the less light it allows to your eye. In Europe, night hunting is popular and so are fixed-power riflescopes because they have fewer lenses and allow more light to reach the eye. Lens quantity also impacts weight because the heaviest component of most riflescopes ends up being the glass. Generally, the more glass there is, the heavier the scope. Variable-power riflescopes weigh more because they have more lenses.
External Adjustments Large dials for reticle movement and parallax adjustment add weight. If you add both to a 30 mm Leupold VX-3HD 4.5-14x40 mm riflescope, weight increases by almost 8 percent and pushes the total weight past a pound. Many hunters who want to shoot at long ranges think these features are mandatory, but are they? Unless you’re shooting past 400 yards, clicking in a ballistic solution is not necessary with modern high-velocity rifle cartridges. Just use a maximum point-blank zero and hold dead on to about 300 yards, then hold a bit higher at 400.
Similarly, the most parallax you can experience with a riflescope is equal to the diameter of the objective lens, at twice the distance at which the parallax is set. So, with a fixed parallax distance of 150 yards and a 40 mm objective, the maximum parallax possible at 300 yards—with your eye as far off center as it could be—is 1 1/2 inches. It’s hard to shoot a rifle with your eye that far off center, and it is hardly enough parallax to matter when shooting at big game at reasonable distances. Additionally, to get a crisp image with a riflescope having an external parallax knob, you must make adjustments, even at distances where parallax is not an issue.
THE LIGHTWEIGHTS The lightweight riflescope is vanishing. Leupold no longer makes the 4x33 mm fixed-power model that was so popular in O’Connor’s day, but the company is still the best source for lightweight riflescopes. For close range or dangerous game hunting, the 2.5x20 mm FX-II Ultralight riflescope is wonderful and weighs only 6 1/2 ounces. The VX-3HD 2.5-8x36 mm riflescope is one of my favorites, and even with the CDS dial system, it weighs less than 12 ounces. Another favorite is Leupold’s FX-3 6x42 mm. Though listed as discontinued on the company’s website, it can still be found in places and offers a great compromise magnification, performs well in low light and weighs 13.6 ounces. I’ve used it for whitetails in the timber, across cornfields in Nebraska and on the Montana plains.
Most other manufacturers have abandoned the concept entirely, but there are exceptions. Swarovski’s 3-9x36 mm scope in the Z3 line is one. This fantastic little riflescope weighs just 12 ounces. My wife used it in Africa, and it worked marvelously out to nearly 300 yards.
The long-range capabilities of heavy riflescopes can be very attractive. The question is—or should be—does the way you hunt require a scope like that, or are you just wanting to play sniper? Just as importantly, do your abilities support the advantages an optic like that can offer? There are still some great options that will serve you well out to around 300 yards, and some weigh less than a box of .30-06 ammo. They’re rugged, hold zero and will make your rifle much easier to carry.