Weaver Base Top Mount #403 - Aluminum Black

The Weaver Base Top Mount #403 Aluminum Black is a precision rifle scope mounting system designed for shooters who demand reliability and accuracy in the field. This top-mount base serves as the critical interface between your rifle receiver and scope rings, making it essential for hunters, tactical operators, and precision rifle enthusiasts. Built to exacting standards, the #403 ensures your optic stays zeroed shot after shot, delivering the stability necessary for consistent performance across hunting, competition, and professional applications.

Crafted from aircraft-grade aluminum and finished in durable black, the Weaver #403 is machined to tight tolerances that guarantee a custom fit on compatible receivers. The precision engineering maximizes clamping force, allowing scope rings to grip securely without marring or shifting under recoil. This rigid construction eliminates play and flex, which are common causes of zero loss and accuracy degradation. The compact design—measuring 3.25 by 0.7 by 4 inches—integrates seamlessly with standard rifle platforms while maintaining a low profile that doesn't interfere with charging handles or accessory placement.

This mount base is ideal for rifle owners upgrading from factory or worn equipment, or building a custom rifle from the ground up. Installation is straightforward for gunsmiths and experienced shooters, requiring only compatible rings and basic tools. The Weaver #403 works with standard Weaver-pattern rings and bases, making it a versatile choice for AR platforms, bolt-action rifles, and other modern sporting rifles. Whether you're mounting a precision optic for long-range shooting or installing a tactical scope for defensive use, this aluminum top mount delivers the foundation your scope system deserves.