Some shooters like to let a professional gunsmith mount a new scope, but you can mount it yourself without any fear of ruing the precision of your rifle. Mounting your scope yourself also means you can fit it to your exact measurements, matching it up to your shoulder for that bespoke fitment.

Incrementally tighten your scope ring screws to our recommend torque-poundage – about 15-18in. lbs, without the use of any thread-locker. If you're mounting horizontally split rings, be mindful of the gaps on either side of the rings, trying to keep them evenly spaced.

Three to 4 inches Properly mounted, a scope should never whack your nose. Can't find the sweet spot, that full circle of light? Your eye is too close to or too far from the ocular lens. Three to 4 inches is about right.

Remember your scope is a precision instrument and just a tiny shift can throw your point of impact off by inches even feet which could cost you a clean shot or cause a miss. If the screws are too tight, they can damage your scope, or the screws can strip making them difficult to next to impossible to remove.

What range is a 3-9×40 scope good for? For this model, a range of 50 yards to 300 yards is ideal.

Our recommendation is no less than 1/8th of an inch of clearance between the bottom of the objective and the top of the barrel. Your second choice (0.160) [for scope base height] will give you enough clearance.

Using tall rings for all your scopes may seem like the obvious solution to this, but it's not the best solution. To get the most out of your scope's range of elevation adjustment, you will need to mount the scope as close (or low) to the receiver as possible. One exception to this is your cheek weld.

Pounds. Then tighten both bottom screws at the same 16 to 18 inch. Pounds. Be sure all screws are tight when. Complete. At this point your rings have been tightened properly. And you're set.

Incrementally tighten your scope ring screws to our recommend torque-poundage – about 15-18in. lbs, without the use of any thread-locker. If you're mounting horizontally split rings, be mindful of the gaps on either side of the rings, trying to keep them evenly spaced.

900 feet The answer is really simple: a 3-9X riflescope provides an additional level of magnification for every 100 feet, all the way out to 300 yards (900 feet). For many years, 300 yards was about the limit of what most big-game hunters considered to be an ethical shooting distance.

For most people who hunt between 50 and 500 yards, a 3-15 magnification range will be more than enough.

Most manufacturers will note the eye relief distance. Most modern scopes have generous eye relief, usually around 3 – 5 inches, giving you plenty of mounting space. Higher magnification, older and rimfire scopes may have less eye relief.

about 3 1/2 inches Eye relief is the distance from the rear lens your eye requires to see a full picture. The industry average for a fixed-power scope is about 3 1/2 inches. For most variables, you'll start out about there at the lower power, and about 2 1/2 inches when you crank up to to max magnifcation.

Depending on the type of cartridge, what type of game you are hunting and the terrain, you may be satisfied with the rifle zeroed at 100 yards. Many times hunters will sight their rifle in an inch or two high at 100 yards so that it will be centered at 200 yards.

If the screws are too tight, they can damage your scope, or the screws can strip making them difficult to next to impossible to remove. That's why scope manufacturers have scope ring torque recommendations.

Most of the companies that make rings and mounts recommend not using Loctite for a couple of reasons. If you use Loctite it may make it hard to take the screws out later if you have a reason or desire to remove them, it may even cause the screw to become hard to remove.