One of the first considerations for buying a riflescope is magnification. As with every other category in this guide, this will first be driven by the intended use of the rifle. A general-purpose hunting rifle should look and feel significantly different than a varmint rifle or dangerous game rifle. Both rifles serve very different purposes and demand different things from a riflescope.
As a general rule, 1x magnification per 100 yards of distance has been the prescription for some time. By that standard, one could adequately take an 800 yard shot with an 8x riflescope. On the contrary, if you’ve looked through a scope at 8x, you’ll soon realize that more magnification is nice to have. That said, the trade-off here is with weight savings and size.
More magnification usually equates to more weight and bigger optics. Big optics can be cumbersome and harder to comfortably strap to a pack. The added weight is also felt on longer trips. Lugging around a 7-35x riflescope would get old quickly on a sheep hunt, so find a magnification range that works best for what you’re doing and you’ll be much better off.
Most riflescopes nowadays are variable-power, meaning they have a magnification range they can be set to like 1-10, 3-18, 5-25, etc.. These ranges are sometimes referred to as Low-Power Variable Optic (LPVO) , Mid-Power Variable Optic (MPVO), and High-Power Variable Optic (HPVO). There are no set rules that define these, but most people discussing LPVO’s are talking about variable-power riflescopes with a maximum high-end magnification under 10x (ex. 1-8x). MPVO’s usually stay under 20x magnification (ex. 3-18x), with HPVO’s encompassing everything over 20x (ex. 5-25x).
Generally, hunting rifles fall within the LPVO and MPVO range, with HPVO’s reserved for aging eyes and extreme long-range hunting. For a dedicated predator rifle chambered in a .22 caliber cartridge like .223 Remington or .22-250, a 1-8x will suffice, but something like a 2-12x might serve you a little better. A big game rifle for deer and elk would probably be best suited with a 3-18x magnification range to accommodate the more capable cartridges typically found in these rifles. Dangerous game rifles generally aren’t intended to shoot beyond a few hundred yards, so LPVO’s or even red dot sights are the way to go if you’re going to run optics at all. The lower power range also helps with target acquisition, so moving targets (like a charging water buffalo) will be easier to obtain a sight picture on.
For all the .338 and larger cartridges, the HPVO’s are usually a better option. Large bore calibers like these have much higher ballistic coefficients and are capable of delivering enough energy to kill an animal at distances beyond 1,000 yards. At these distances, more magnification is necessary to make reliable hits. While this type of hunting is rare, there are some folks who do it. For the more common use case, aging hunters or folks with less capable vision may opt for higher magnification at shorter distances to compensate for their suffering eyesight.