September 23, 2010
By Wayne van Zwoll
Midrange variables may be fine most of the time, but big scopes have their place.
By Wayne van Zwoll
The author's not exactly changing his tune, but even he admits scopes such as the 6.5-20X Nitrex can mean all the difference when you have to reach out for a long shot.
Asked why he preached pretty much the same sermon Sunday after Sunday, the pastor threw the question back. "If I asked you how to catch a bass or kill a deer, would you answer differently next week?"
I still think most rifles wear scopes several sizes too big, and in most cases hunters would be better off using less magnification. With one exception, I can't think of a big game animal I've shot that couldn't have been taken handily with a 6X scope--and that was a 410-yard shot on a Coues deer many years ago.
This shot would have been tough with a low-power sight, partly because a Coues buck is not much bigger than a healthy northern coyote but mainly I needed all the resolution I could get.
Why am I not a big fan of large-power scopes? Stiff recoil can cause a heavy scope to slip in the rings, even shear screws. Further, large objective bells the size of coffee mugs mandate high rings, so your cheek loses firm contact with the comb. And the weight of a big scope is no fun to carry and also moves its center of gravity out of your hands, impairing balance and slowing your aim.
The good news is that high magnification has become lighter and more compact. Now you can get a powerful sight that looks good on a carbine or a svelte mountain rifle.
Traditional variables had "three times" magnification. The magnification range of the standby 3-9X with one-inch tube is shared by the 1.5-4.5X, 2.5-8X, 4-12X and 6.5-20X.
The 30mm tube enabled scope engineers to boost range to "four times." So we got the 1.5-6X, the 2.5-10X, the 4-16X. Now there are "five times" scopes such as Swarovski's Z5, a one-inch scope with the eminently useful power range of 3.5-18X. Swarovski also has the 30mm Z6 line.
The reason magnification range matters is that you don't want the low-end power pulled above a reasonable floor by high magnification at the top. A 6-18X scope has a useful range. But there are times--in close timber under dark skies--when 6X offers too tight a field, too small an exit pupil. A 3.5X bottom gives you much more versatility.
Still, you must mind physical dimensions. Scope companies march like zombies along the path to ever-bigger front lenses. Someone must be buying them. It isn't me. Though saucer-size objectives give you a bigger exit pupil and higher resolution, all else equal, all else is seldom equal. That is, the superb lens coatings used on the best Leupold, Zeiss, Swarovski, Schmidt & Bender and Nikon scopes set standards for both image quality and brightness. Though the performance gap between these and less expensive scopes has narrowed of late, you can't expect top-end images from bargain-priced optics.
Then, too, a modest objective--say, 40mm or even 36mm--transmits more light than even a healthy eye can use to advantage in the dimmest field conditions at 6X. If you need an exit pupil greater than 6mm (objective diameter divided by power), check your watch. It might be too late to shoot.
But if you're addicted to acres of glass up front, consider Leupold's relatively new VX-7L, whose lens shape allows you to mount a 50mm objective as low as a 36mm round bell and a 56mm as low as a 40mm. Low mounting is an advantage not to be overlooked. It puts your eye closer to the barrel, keeps the rifle's center of gravity well inside your hands. Also, if you're shooting steeply uphill or down, the low-mounted scope requires less adjustment in your aim.
Greater magnification range is only one of several innovations that make high-power scopes better choices now than in years past. Most reticle development has centered on long-range shooting. Makers have also shifted reticle location to the second (rear) focal plane in deference to American tastes.
With second-plane reticles (behind the magnifying lenses), target subtention changes as you change power. Reticles in the first focal plane (popular in Europe) change apparent size with power shift but stay in constant relationship with the target. Hunters Stateside like the rear-plane reticle because it covers less of the target at high power, and it is easy to see at low power.
If you're gearing up for long shots, you can choose from a few simple and many complex reticle designs. Simple is generally better on a hunt because it's conducive to fast, mistake-free shooting. I favor the Burris and Swarovski plex reticles with simple graduated ladders on the bottom leg. They're useful out to 500 yards for most cartridges--farther than I can shoot accurately under most field conditions.
Of the more sophisticated reticles, I like Darrell Holland's design (hol landguns.com), which he has installed in Leupold and Schmidt & Bender scopes. It is relatively clean but gives you both mil and minute-of-angle reads out to extreme range.
Still, unless you do a lot of shooting at long range, you may be better served with one of myriad midrange variables. Yes, I'm still delivering the same sermon, but you never know when a buck will slip from the shadows very far away, and a bigger scope can help you make that shot.