Leupold Mark 4 One-Piece base, Browning A-bolt SA, 20 MOA

• 20 MOA inclination: The built-in forward cant preserves more scope elevation for dialing at longer distances, which is especially useful on rifles set up for extended-range shooting.
• One-piece steel construction: A single steel base adds rigidity across the action and gives the optic a stable mounting platform that stands up well to recoil and hard field use.
• Cross-slot interface: The Picatinny-style slot layout supports secure ring engagement and makes it easier to position compatible optics for proper eye relief.
• Model-specific Browning A-Bolt SA fit: This base is made for the Browning A-Bolt Short Action pattern, helping simplify installation and maintain correct alignment on the receiver.
• 8-40 adaptable design: The base is built around a robust mounting pattern that suits serious rifle setups where dependable screw engagement matters.

About the Mark 4 Series

Leupold Mark 4 products are built for shooters who need a mounting and optics system with a strong emphasis on repeatability, durability, and practical field use. Within Leupold's lineup, the Mark 4 name is closely associated with tactical and precision-oriented equipment, including riflescopes and mounting solutions designed to support hard use on rifles set up for disciplined shooting. The series focuses on straightforward mechanical design, robust materials, and interfaces that stay secure under recoil and frequent handling.

In the mounting category, Mark 4 bases are intended to provide a stable link between rifle and optic, with configurations tailored to specific actions and shooting roles. One-piece rails, cross-slot geometry, and canted options for additional elevation are all part of that approach. Rather than adding unnecessary complexity, the series concentrates on the fundamentals that matter most: keeping the optic firmly in place, maintaining alignment, and giving the shooter a dependable platform for precision work. That makes the Mark 4 family a natural fit for tactical optics, long-range rifles, and hunting or target setups where consistent scope mounting is critical.

About the Leupold Mark 4 One-Piece base, Browning A-bolt SA, 20 MOA

The Leupold Mark 4 One-Piece base for the Browning A-Bolt SA is a purpose-built scope base for shooters who want a stronger mounting platform and additional elevation for longer-range work. Its 20 MOA inclination tilts the optic slightly forward, allowing more usable upward adjustment in the riflescope. In practice, that means a rifle can be set up with more dialing range available before the scope reaches the top of its internal travel, which is valuable for precision shooting at distance.

The one-piece steel construction adds stiffness across the receiver and gives compatible rings a solid, continuous surface to clamp onto. Steel is a sensible choice for a rifle that may see repeated recoil, transport, and regular optic changes, because it prioritizes strength and secure thread engagement over minimum weight. The cross-slot rail pattern also makes ring placement more flexible, helping the shooter position the scope correctly for eye relief while keeping the setup firmly locked in place.

Because this base is made specifically for the Browning A-Bolt Short Action, it suits rifles that need a clean, model-matched mounting solution rather than a universal compromise. The matte finish keeps the appearance subdued, while the low 4.00 mm BH height helps maintain a close-to-bore mounting geometry. For a precision hunting or target rifle built around a short-action Browning, this base provides the mechanical foundation needed for a dependable optic setup.

About Leupold

Leupold & Volpel was founded in Portland, Oregon, in 1907 by Fred Leupold and Adam Volpel. The company later expanded into sporting optics and introduced its first riflescope, the Plainsman, in 1947, establishing the direction that would define the brand. In 1968, Leupold moved its manufacturing plant and headquarters to Beaverton, Oregon, where the company remains based today.

Leupold & Stevens, Inc. is known for developing sport optics for hunting, shooting, and outdoor use, with product lines that include riflescopes, red dot sights, binoculars, spotting scopes, rangefinders, and thermal optics. The brand is also closely associated with tactical and precision-oriented riflescopes through its Mark-series products, while the VX-series remains a core part of its hunting optics range. That broad experience in riflescopes and mounting systems makes Leupold a well-established name for shooters who want compatible optics and mounting hardware from the same manufacturer.

Main Features

• Manufacturer: Leupold
• Made in: USA
• Material: Steel
• Color: Matte
• BH height: 4.00 mm
• Inclination: 20 MOA
• Base configuration: 1-piece
• Weight: 4.4 oz
• Compatibility above: Picatinny Rail
• Compatibility below: FN Browning A-Bolt SA, FN Browning Eurobolt SA, FN Browning A-Bolt II SA

Warranty

Leupold provides a 10-year warranty for this base. That stated period gives added reassurance for a component that plays a critical role in keeping the optic secure and properly aligned on the rifle.