How to Mount a Rifle Scope: Rings, Torque Specs and Leveling

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Mounting a rifle scope onto your rifle's existing factory bases or rail is a straightforward job if you take it slow, torque things properly, and level the reticle before you snug everything down. This guide covers mounting an optic to bases/rails already on your rifle — no drilling, no gunsmithing, no changes to the rifle's function.

What you need

You don't need a full gunsmithing bench, but a torque driver and a leveling reference will save you from stripped screws and a canted reticle. Prices below were checked Nov 11, 2026.

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Step 1: Safety first

Before you touch a screwdriver, unload the rifle. Open the action and visually and physically verify the chamber is empty, and check that the magazine is empty too. Keep ammunition out of the room while you work. Treat the rifle as if it's loaded the entire time.

Step 2: Bases and rings

Your rings need to match both your base or rail and your scope's tube diameter. Base screw torque follows whatever the base manufacturer specifies — don't guess. A few published examples: Leupold STD bases call for 22 in-lb on 6-48 screws and 28 in-lb on 8-40 screws, with windage screws at 45 in-lb and ring screws capped at 28 in-lb; Ruger 10/22 bases run 12-15 in-lb; Browning X-Bolt bases run 18 in-lb (Leupold STD mounting instructions). Warne notes base screws are usually capped around 25 in-lb for a steel receiver and roughly 15 in-lb for aluminum (Warne torque guide). If your base or receiver isn't listed in either source, use the number printed in your base's own instructions.

Step 3: Set eye relief

Per Leupold, start with the scope slid as far forward in the rings as it will go. Shoulder the rifle naturally, in your normal shooting position, and slide the scope rearward until you see a full, unshadowed sight picture. If your scope is a variable, set eye relief at the highest magnification setting, since eye relief typically shrinks as power increases.

Step 4: Level the reticle

Leupold calls a dedicated leveling system highly recommended, and it's worth the small investment. The basic method: rest one level on a flat reference surface of the rail or action (not the barrel, which can taper), and a second level on a flat part of the elevation turret cap, then rotate the scope in the rings until both levels agree. A kit like the Wheeler Professional Reticle Leveling System does this with a reference level and a barrel-clamp level built for the job, which is easier than balancing two separate levels by hand.

Step 5: Torque the ring caps

Warne's guidance is to snug the ring cap screws to about 10 in-lb first, just enough to hold the scope in place without locking it. Then tighten in stages, working in a crisscross pattern across the screws, checking that the gap between the ring top and ring bottom stays even on both sides as you go — an uneven gap usually means the scope is being pinched crooked. Ring cap screws run dry; Warne's instructions do not call for thread locker on them (Warne how-to).

Final ring torque depends on both the ring and the scope maker's limits. Examples: Leupold STD rings cap at 28 in-lb; Leupold BackCountry cross-slot rings call for 28 in-lb on the cap, 45 in-lb on the ring bottoms, and 22 in-lb on the base (Leupold BackCountry instructions); Vortex Pro 1-inch rings call for 12-15 in-lb on ring screws and 25 in-lb on the base clamp. Warne notes 20-25 in-lb used to be the standard figure, though some lightweight scope tubes call for as little as 15 in-lb. The rule that matters most: whenever the scope manufacturer's limit is lower than the ring manufacturer's limit, use the lower number.

Step 6: Bore-sight and zero at the range

Once everything is torqued and level, bore-sight the rifle if you have the means, then head to the range to confirm and finish your zero. If you're still deciding on glass or want to understand your reticle's units before you dial, see our guides on MOA vs MRAD and how to buy a good scope on a budget.

Common mistakes

• Over-torquing ring or base screws past the maker's stated maximum, which can crush a scope tube or strip threads.
• Skipping the leveling step and eyeballing a canted reticle, which shows up as a drifting zero at longer range.
• Using the wrong ring height for your objective bell or action, causing clearance or cheek-weld problems.
• Leaving uneven gaps between ring caps and ring bottoms, a sign the scope is clamped crooked.

Shopping for a scope?

If you haven't bought glass yet or are eyeing an upgrade, check our roundup of best rifle scopes under $500 for Black Friday 2026 and keep an eye on daily deals for current pricing.

FAQ

What torque should scope rings be?

It depends on the ring and scope manufacturer — there's no single universal number. Use the examples above as reference points and always defer to the lower of the two makers' published specs.

Do I need a torque wrench?

Not strictly, but it's the easiest way to avoid stripping screws or crushing a scope tube, since factory specs are often tighter than what "feels right" by hand.

Should I use thread locker on scope rings?

Per Warne, ring cap screws are meant to run dry with no thread locker. Base screws should follow whatever the base manufacturer specifies for that application.

How do I know my scope is level?

Reference a flat surface on the rail or action with one level and a flat spot on the turret cap with another, or use a dedicated leveling kit like the Wheeler Professional Reticle Leveling System, and adjust the scope in the rings until both agree before final torque.