How to Mount a Rifle Scope the Right Way
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By Peter Makulek · Senior Optics Editor · · Live prices from US retailers
Quick answer: most scope rings require 15–18 inch-pounds of torque on the ring caps, and most bases require 25–65 inch-pounds depending on the fastener — always check the manufacturer's spec sheet first. Use a quality FAT (inch-pound) wrench, a bubble level or plumb-bob, and medium-strength (blue) threadlocker on the base screws. Getting these three elements right — torque, threadlocker, and leveling — eliminates 90% of the tracking errors, zero shifts, and scope damage that plague new rifle builders.
Mounting a scope is the most consequential step between buying good glass and actually shooting well. A $2,000 Nightforce or Schmidt & Bender optic will perform like a $100 bargain bin scope if it is canted, over-torqued, or sitting in rings that flex under recoil. Every year, US shooters damage ring lugs, strip turret housings, or chase phantom zero shifts because they skipped a $30 torque wrench or eyeballed the level. This guide gives you the exact procedure, tool list, and specs so you get it right the first time — whether you are mounting a Vortex Viper on a deer rifle or a March on a PRS rig.
The US shooting market now spans an enormous range of platforms: bolt guns in 6.5 Creedmoor and .308 Winchester, AR-10s and AR-15s in .223/5.56, long-range magnums in .300 PRC, and rimfire trainers in .22 LR. Each platform has its own base type (Picatinny, Remington 700 two-piece, integral rail) and its own recoil profile, which directly affects how much threadlocker you need and how carefully your ring torque must be dialed in. We will cover all of them.
This guide is organized for both first-timers and experienced shooters who want to double-check their process. We cover tools first, then base and ring torque specs, then the Loctite question, and finally three distinct methods for leveling your reticle. At the bottom you will find product picks for mounting accessories, an in-depth buying-advice section covering budget tiers and common mistakes, and a thorough FAQ.
Top Picks — Live US Prices
Sightron SIII10-50x60mm Tactical Windage .05MIL, 1.2 MIL L-R, Black, 10-50x60 Tactical Windage .05MIL 1.2, 75003
via OpticsPlanet
$64.99
Sightron SIII8x32mm/SIII6x24mm Tactical Windage Knob MOA, 7L-7R, Black, 8-32 and SIII6-24 Tactical Windage Knob MOA 7L-7, 75002
via OpticsPlanet
$64.99
Sightron SIII10 50x60mm Tactical Windage MOA, 5L-5R, Black, 10-50x60 Tactical Windage MOA 5L-5, 75001
via OpticsPlanet
$64.99
Buying Advice
Key specs to check before you buy rings and bases: Tube diameter matters most — a 30mm scope needs 30mm rings, not 1-inch, and a 34mm tube (common on high-end Nightforce, March, and S&B optics) needs 34mm rings that are harder to find cheap. Ring height is the second critical number: measure the gap between the top of your barrel or rail and the center of the bore, add half the objective bell diameter, and leave at least 1/8-inch of clearance. Too-low rings let the bell contact the barrel; too-high rings force an uncomfortable cheek weld. Most Picatinny-rail bolt rifles work well with medium-height rings for objectives up to 44mm and high rings for 50mm or larger.
Budget tiers break down roughly into three bands. Entry-level ($20–$60) includes Vortex Pro rings, Burris Zee rings, and Weaver-style two-piece bases — perfectly adequate for hunting rifles that see moderate recoil and will not be removed frequently. Mid-range ($60–$180) covers precision aluminum rings like the Vortex Precision Matched, Leupold Mark 4, and Burris XTR Signature series, which use alignment inserts or lapping surfaces for better concentricity. Premium ($180–$400+) means Nightforce X-Treme Duty, Spuhr mounts, and American Rifle Company M10 rings — machined to extremely tight tolerances, often with built-in MOA cant for long-range shooting, and designed for repeated removal and return to zero.
The most common mistake is over-torquing ring caps. Scope tubes are relatively thin aluminum; exceeding 20 inch-pounds on most ring caps can dent the tube, create stress risers, and crack internal erector assemblies — especially on mid-price scopes from Bushnell, Vortex Crossfire-tier, or older Nikon models. Always torque in a cross pattern (like lug nuts) and sneak up on the final value in 3–5 inch-pound increments. The second most common mistake is uneven ring-cap gaps: both sides of each ring cap should show identical gaps when you are done. If one side is closed and the other is open, the scope tube is being pinched, which will bind the erector and ruin tracking.
For US shooters, the discipline dictates the mount setup. A whitetail hunter in the East, shooting under 150 yards from a tree stand, can use lightweight aluminum rings and a two-piece base — the rifle comes out of the safe a few times a year and recoil is moderate (.30-06, .308, .243). A PRS competitor running a 6.5 Creedmoor at 500–1,200 yards needs a one-piece 20-MOA canted rail, precision rings or a one-piece mount, and absolute confidence in return-to-zero. An AR-15 varmint shooter in the West needs a cantilever mount that moves the scope forward for correct eye relief on an AR-length receiver. Buy from Amazon.com or OpticsPlanet where you can verify ring specs and return if the fit is wrong.
Brand landscape for mounting hardware: Vortex offers the widest spread from entry (Pro rings ~$40) to mid-tier (Precision Matched ~$100–$150), and they carry their VIP warranty to rings and bases. Leupold's Backcountry, Mark 4, and Mark 5 ring lines are staples on hunting rifles coast to coast. Nightforce's rings and the Nightforce Unimount are considered the gold standard for tactical/PRS use. Burris XTR Signature rings use offset polymer inserts that compensate for minor base misalignment — a clever solution that eliminates the need for lapping. Spuhr (Swedish-made but widely available in the US) is the premium one-piece mount of choice for military-pattern rifles. For budget builds, Wheeler makes inexpensive but effective scope-mounting kits that include a FAT wrench, lapping bars, and alignment rods — an excellent starting point for someone setting up their first rifle.
Frequently Asked Questions
What torque in inch-pounds should I use for scope ring caps?
Most manufacturers specify 15–18 inch-pounds for ring-cap screws. Nightforce recommends 15 in-lbs for their rings; Vortex typically calls for 15–18 in-lbs; Leupold often specifies 15–17 in-lbs. Always check the spec sheet that ships with your specific rings, because values vary by fastener size and ring material. Over-torquing is the single most common cause of scope damage during mounting.
What torque do I use for scope base screws?
Base-screw torque depends on the screw size and base type. Typical Remington 700 base screws (6-48 thread) call for 25–28 in-lbs, while Picatinny rail screws using 8-40 threads often require 30–65 in-lbs. Savage AccuTrigger-era action screws differ from older models. Always consult the base manufacturer's printed torque spec, not a generic chart, because thread pitch and material hardness vary.
Should I use Loctite on scope mount screws, and which color?
Use blue Loctite 242 or 243 (medium-strength, removable) on base screws — these experience the most recoil stress and benefit from threadlocker. Most ring-cap screws do not need Loctite if torqued correctly, and some manufacturers explicitly advise against it on ring caps to avoid over-clamping the tube. Never use red Loctite (271, permanent) on any scope-mounting hardware; you will strip screws or crack the base trying to remove them later.
What tools do I need to mount a scope at home?
At minimum: an inch-pound FAT (Firearm Adjustment Tool) wrench or a small click-type torque wrench with a bit set (Torx T-15, T-20, T-25, and hex bits), a set of scope rings matched to your tube diameter, a scope base matched to your action, a bubble level or plumb line, and degreaser (90% isopropyl alcohol works well). A Wheeler FAT wrench kit or Vortex Torque Wrench covers most mounting tasks for under $40. Lapping tools, alignment rods, and feeler gauges are optional but useful for premium setups.
What are three ways to level a rifle scope reticle?
Method one: a segmented-crosshair or plumb-bob method — hang a plumb line at 25 yards, level the rifle in a vise, and rotate the scope until the vertical crosshair aligns with the string. Method two: use a barrel-clamp bubble level on the flat of the action or rail and a second small bubble level on the scope's elevation turret cap; adjust the scope until both read level simultaneously. Method three: a precision scope-leveling tool like the Wheeler Professional Reticle Leveling System, which clamps to the action and projects a reference grid you match to the reticle. Method two is the fastest; method one is the most traditional; method three is the most repeatable.
Do I need a 20-MOA canted base, and what does it do?
A 20-MOA base tilts the scope's optical axis downward relative to the bore, giving you roughly 20 extra MOA of elevation adjustment for long-range shooting. If you plan to shoot beyond 600 yards with a 6.5 Creedmoor or beyond 800 yards with a .300 PRC, a canted base helps ensure you do not run out of internal elevation travel. For hunting under 400 yards, a standard 0-MOA base is usually sufficient and keeps your zero closer to the scope's optical center, which can improve image quality and tracking.
Can I mount a scope on an AR-15 flat-top without special tools?
Technically yes — a Picatinny cantilever mount clamps directly to the AR-15 flat-top rail with cross bolts, and many use a single nut or pair of bolts. However, you still need an inch-pound torque wrench to avoid over-tightening. Eye relief on an AR-15 with a collapsible stock is shorter than on a bolt gun, so a cantilever mount that moves the scope forward 2–3 inches is strongly recommended. Verify any specific mount's availability on Amazon.com, as some accessories that attach to firearm receivers may face listing restrictions.
How do I know if my rings are the right height?
Place the scope in the bottom halves of the rings (without the caps) and visually check clearance between the objective bell and the barrel or handguard. You want at least 1/8 inch of gap — enough to slide a couple of business cards through. If the bell touches, you need taller rings. If the rings are so tall that you cannot get a comfortable cheek weld without lifting your head off the stock, consider lower rings or a cheek riser. Ring-height calculators from Vortex, Leupold, and Burris are available free online and are accurate for most common rifles.
Is it worth paying a gunsmith to mount my scope?
For a first-timer, a competent gunsmith will mount, lap, level, and bore-sight your scope for roughly $40–$75 — money well spent if you lack a torque wrench and level. However, learning to do it yourself is a valuable skill, especially if you own multiple rifles or compete in PRS where you may swap optics seasonally. A one-time investment in a Wheeler or Vortex mounting kit ($30–$50) pays for itself after two mounts and gives you the confidence to verify your setup in the field.
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