Technical

How to Mount an LPVO

By Joe Kriz

04/16/2024

For gun owners who have never done it before, mounting a low power variable optic (LPVO) can seem as daunting as shooting with one for the first time. Like the wheels on your car, riflescope mounts are integral to the stability and performance of the optic they hold. But, when armed with the right tools and technical knowledge of how to select a mount and properly secure an optic, mounting can be a quick and easy task you may even learn to enjoy.

Selecting A Mount


Before you can mount your optic, you need to select a mount. You may be tempted to grab the first mount you find at your local dealer, but there are numerous factors to consider to ensure your mount complements you and your LPVO.

Mount Style

Riflescopes can be mounted in either one-piece/cantilever mounts with integrated scope rings, or in two independent scope rings. Both mount styles can be used on flat-top AR-style, but scope rings are more common on bolt-actions with disconnected mount bases.

Tube Diameter

Regardless of style, all riflescope mounts will use rings to clamp the LPVO body/tube in place. Scope tubes and mounts are offered in three common diameters: 1 inch (25.4mm), 30mm, and 34mm. Make sure the rings of your chosen mount are sized accordingly to fit your LPVO.

Cantilever Offset

Cantilever mounts have varying offset lengths – or the position of the rings in relation to the base. Offsets can range from zero (0) to 3 inches, with longer offsets positioning the LPVO farther forward. A longer rifle length of pull (LOP) will require a larger ring offset.

Mount Height

Cantilever mounts and scope rings can also be had in different heights to accommodate different rifles (AR-style vs. bolt-action) and shooting positions (standing vs. bench vs. prone). You’ll want to mount your scope as close to the bore as possible without it touching the rifle.

Attachment Method

There are two ways to fasten a one-piece scope mount to a rifle: bolts and quick-detach (QD) levers. QD – or tool-less – mounts use spring-tensioned levers to allow quick removal of optics from a firearm while bolt base mounts require the use of Allen keys or torque wrenches.

Mount Weight

If you’ve ever lugged a rifle around on a hunt, you know how heavy firearms can be. Weight savings can often be gained in optic mounts, with scope rings, skeletonized cantilever mounts, and aluminum construction helping shed crucial ounces for those who need or want it.

Offset Capability

The last factor to consider is the ability to add an offset (45-degree) or piggyback (12 o’clock) pistol red dot to your scope mount. Some LPVO mounts feature integrated mounts for secondary optics while others can be added via replacement ring caps or as separate rings.

What You’ll Need


To mount your LPVO, you’ll need the following components and tools:

  • Rifle (AR-style or bolt-action)
  • Low power variable optic (LPVO)
  • Optic mount or scope rings
  • Work bench or flat surface
  • Gun or bench vise
  • Torpedo or I-beam/box bubble level (minimum 12” long)
  • Small level(s) (bubble or digital)
  • Torque wrench/driver (with bits)

Safety Tip: When handling firearms, safety is always of utmost importance. Before mounting, confirm your rifle is clear by removing any loaded magazine and visibly checking the chamber for ammunition. If desired, insert a chamber flag as a signal to you and anyone else in the room that the rifle is safe.

Now that you’re confirmed clear, let’s get to optic mounting.

How to Mount Your LPVO


The following steps assume the use of a one-piece/cantilever mount. Using scope rings may add additional steps to mount and level your optic.

1. Level work surface

Leveling is a constant theme of optic mounting and starts with your work surface. Whether working off a bench in your garage, your kitchen table, or the bed of your pickup, ensure your work surface is as flat as possible. This will provide a level foundation to work off of when leveling your rifle and optic in future steps.

First, remove any unnecessary objects from your chosen surface and wipe off any debris to give yourself a clean and uncluttered area to work. Then, take a torpedo bubble level or longer I-beam/box spirit level (preferably 12” or longer) and lay it across the work surface. The surface should be level both left to right and front to back. If your table surface has legs, you may need to add shims.

Quick Tip: Avoid working off cardboard, carpet, and surfaces on casters/wheels. Your work surface should be solid in material and design to avoid movement and becoming unlevel as you mount.

2. Prepare mount and optic

After leveling your work surface, you want to prepare your rifle, mount, and optic. If you haven’t already, start by removing any loaded magazine and double-checking the rifle chamber for ammunition.

Grab your mount and loosen the bolts that allow the base to clamp to the rifle’s receiver. You don’t need to remove the bolts entirely from the mount. Then, loosen the screws that attach the top ring caps to the rest of the mount and remove the top caps, setting them aside. Again, the screws don’t need to be completely removed from the rings.

Next, remove any accessories from your LPVO, including lens caps, sunshades, and magnification rings, which may alter the optic’s balance or get in your way when mounting. These can be reattached after mounting the scope. Finally, check your rifle, mount, and optic for any dirt, dust, metal burrs, or abnormalities that may affect mounting.

Quick Tip: Optic mounting is a perfect opportunity to also inspect and clean your firearm. Check that all parts and accessories are tight, functioning properly, and not damaged. Wipe down the outside of your rifle and add lubricant to metal-to-metal contact and wear points inside, if needed.

3. Establish eye relief

When mounting a rifle optic, the optic’s position on the firearm in relation to your head/eye when shooting – or eye relief – is critical to obtaining a clear and repeatable sight picture. But rather than wait until after the mount and optic are torqued down to confirm eye relief, you can establish your preferred eye relief beforehand.

If you plan to attach backup iron sights (BUIS) to your rifle, install these (or at least the rear sight) before proceeding.

Place the mount on the rifle receiver/rail section and position the optic in the open mount saddle with the turrets centered between the front and rear rings. You may need to lightly hand-tighten the mount’s base bolts to prevent it from falling off. While securely holding the optic in the mount, pick up the rifle and obtain a cheek weld that matches how you normally, or intend to, shoot. Carefully move the mount and optic, as one, forward and backward until you achieve a preferred sight picture without scope shadow.

Visually take note of and/or physically mark the rear position of the optic mount, assuring it falls within slots of the Picatinny rail receiver, and set the rifle, mount, and optic down on your work surface. This is where you’ll attach the mount in upcoming steps.

Quick Tip: If mounting to an AR-style rifle and unable to confirm eye relief using this method, align the back of the LPVO ocular assembly with the charging handle/back of the receiver. This should get you close enough until you can confirm positioning on the range.

4. Secure and level firearm

While you can mount optics using a mounting station separate from your rifle, like the Short Action Customs Final Scope Level, we prefer to mount directly on our firearm. To do so, we first need to secure the rifle on or to our work surface using a vise.

Two types of vises can be used to secure firearms for optic mounting. The first, a gun vise, is specifically designed to hold your rifle while cleaning, optic mounting, or zeroing on the range, using padded rests to support the buttstock and handguard/barrel in place. Alternatively, you can use a standard bench vise attached to your work surface. For AR-style rifles, a magazine well vise block attachment can be clamped in the vise jaws and inserted into the rifle for support. Bolt-action rifles can be carefully clamped using a towel or soft jaw inserts that won’t scratch or mar the stock.

Whichever style vise you use, you’ll need to level your rifle in place. Gun vises often feature adjustable height rests and feet for easy leveling, while bench vises require manual trial and error to perfect. Place a level on the rifle receiver or Picatinny rail section and adjust as needed before locking the rifle in place.

Quick Tip: Instead of clamping a complete AR-style rifle in your bench vise, separate the barreled upper from the lower receiver. Then, clamp the upper receiver directly in the vise jaws (with a towel or soft inserts) or using a special AR upper vise block and continue mounting.

5. Secure mount to firearm

Now that your rifle is secure and level, we can finally get to mounting the optic itself – beginning with the scope mount.

Using the eye relief reference point we found in Step 3, position the mount on the rifle receiver or Picatinny rail section and hand tighten the base clamp bolts. If using a cantilever mount, the forward cant should be toward the rifle’s muzzle. Then, simultaneously push down on and against the mount in the direction of cant while tightening the bolts with your torque wrench. This helps engage the mount against the receiver rail.

Once torqued to spec, confirm there is no movement in the mount.

Quick Tip: Tighten the mount’s rear most base clamp bolt first and work your way toward the muzzle. Refer to manufacturer specs for proper torque and be careful not to over tighten the bolts to avoid stripping, cross threading, and snapping their heads.

6. Position optic in mount

Place your LPVO in the secured mount with the turrets centered in the saddle between the front and rear rings. The larger ocular/magnification assembly should be closest to the rifle’s buttstock.

Drop the top ring caps over the optic tube and tighten the cap screws just enough to engage with matching holes in the mount. Do not tighten them completely, as you’ll torque them in the next step.

Place a small level on the optic’s elevation/top turret. Turret caps may need to be removed to find a flat enough surface to level. Align the level atop the turret with the barrel and check for level. If not level, double check that your rifle and work surface are still level before adjusting the optic’s horizontal position/balance within the saddle. Wedges can also be used to level the mount. Once level front to back, rotate the level atop the turret 90-degrees so it lays perpendicular to the barrel. Check for level side-to-side, slightly rolling the optic in the rings until achieved.

Once you find level in both directions, try not to bump or move the optic, rifle, or work surface.

7. Secure optic in mount

With the optic leveled in the mount, you’re ready to lock it in place. But like tightening lug nuts on a car tire, there is an order to the madness.

Most one-piece/cantilever mounts have four screws per ring for a total of eight screws. Two screws sit on each side of the optic body per ring. Whichever side of the firearm/optic you’re standing on, start by fastening the top left screw on the left ring (#1) – but don’t torque to final spec just yet. Then, cross over diagonally and tighten the bottom right screw on the same ring (#2). This is the first of four crossovers you’ll complete that will eventually form an X pattern on both rings.

Jump over to the right-side ring and tighten its top left screw (#3) followed by the screw on the bottom right (#4). Tighten the screw directly above it on the other side of the optic body (#5) before tightening the screw diagonal to it (#6). Move back to the left ring and tighten the two remaining screws (#7, #8), top to bottom. If done properly, the gap between the top and bottom halves of each ring should be even.

Next, repeat the same pattern in order, torquing each screw to manufacturer spec while maintaining even ring gaps. Don’t tighten beyond spec or you may mar or crush the optic tube.

Quick Tip: If you forget the screw tightening pattern, just remember not to tighten both screws on one side of a ring cap right after the other. This often makes it more difficult to achieve an even clamp and top-bottom ring gap. It’s best to tighten in an X pattern with even and consistent torque.

9. Mount offset red dot (Optional)

Though LPVOs have a low-end magnification of 1x, the reality is it’s not a “true” 1x like that of a pistol red dot. As such, many shooters will pair their variable optic with an offset or piggyback red dot using integrated or separate mounts.

If using an offset red dot, mount it to your rifle after mounting your LPVO. No leveling is required to mount an offset or piggyback dot sight.

Swampfox Optics


As an optics manufacturer, we know a thing or two about mounting LPVOs. Whether you need a mount for your optic, an optic for your mount, or both, we have a wide-range of cantilever mounts, scope rings, and SFP and FFP low power variable optics to choose from.

LPVO Mounts

Swampfox Cantilever Mounts

Swampfox offers three types of cantilever scope mounts perfect for mounting LPVOs. All one-piece mounts, our Independence Mount provides a solid and sturdy platform specifically for 30mm tube optics with a 1.5” centerline height. Freedom and Hostile Engagement Mounts are similar in style, both featuring skeletonized designs for weight savings and accommodating 30mm and 34mm riflescopes with 1.6” centerline heights. Our HE Mount also integrates four 45-degree RMR footprint offsets (two per ring) for direct mounting of secondary red dots.

Swampfox Scope Rings

For shooters who need or prefer scope rings, we also have you covered. Essentially taking the ring sections from our Freedom and HE Mounts, our Freedom Rings II and Hostile Engagement Rings offer rugged versatility for mounting 30mm and 34mm tube LPVOs at 1.10”, 1.60”, and 1.93” heights to bolt-actions and rifles builds where every once counts. Like our mount of the same name, HE Rings integrate two RMR footprint mounts per ring for offsetting red dots.

Shop Swampfox Mounts & Rings

LPVOs

Swampfox Arrowhead

Excellent in all applications, every quiver should include an Arrowhead LPVO. Push/pull locking turrets protect against unintentional adjustment while its 30mm tube and 24mm objective lens offers a wide field of view and sharp resolution. Arrowhead is available in three magnification ranges and SFP reticles, each with 12 red or green illumination settings for shooting in any light.

Shop Swampfox Arrowhead

Swampfox Tomahawk II

Built on the foundation of our original riflescope, Tomahawk II embodies user feedback with enhanced features, now offered in 1-4x and 1-6x ranges and equipped with an SFP BDC or new Bright Fiber Optic reticle. Constructed on a 30mm tube, it reflects the evolved preferences and needs of today’s shooters, marking a significant advancement in our LPVO lineup.

Shop Swampfox Tomahawk II

Swampfox Warhorse

Warhorse 1-6x is the first of our premier First Focal Plane (FFP) LPVO series. With smooth magnification and edge-to-edge clarity, Warhorse combines speed and precision for rapid target acquisition at any distance. Its compact 34mm tube design features a push/pull locking elevation turret with zero reset, capped windage turret, and 12-position illumination turret.

Shop Swampfox Warhorse

Get free shipping on any order over $300 – perfect for any LPVO and mount combination. Plus, try Swampfox LPVOs risk-free with our 30-Day Money-Back Satisfaction Guarantee. If left unsatisfied after 30 days, simply return your optic and exchange it for another or a full refund.