Weaver 48018 Top Mount Base - Marlin 88/89/98 Remington 12A/121

The Weaver 48018 Top Mount Base delivers rock-solid scope mounting for classic rimfire rifles including Marlin 88, 89, 98 and Remington 12A, 121 models. This precision-machined base transforms vintage .22 caliber rifles into accurate hunting and target platforms by providing a stable foundation for modern optics.

What Makes This Different

Unlike generic aftermarket bases, the Weaver 48018 features rifle-specific machining that matches the exact receiver contours of supported firearms. The base maintains proper scope height while ensuring consistent eye relief across different magnification settings. Premium steel construction withstands repeated mounting cycles without losing zero, outperforming aluminum alternatives that can strip or deform under stress.

Key Features

• Precision-machined steel construction for maximum durability and zero retention
• Rifle-specific design fits Marlin 88/89/98 and Remington 12A/121 receiver profiles
• Matte black finish resists corrosion and reduces glare in field conditions
• Standard Weaver-style cross slots accept most ring systems and accessories
• Low-profile design maintains proper scope height for comfortable shooting
• Factory-drilled and tapped mounting holes ensure precise installation
• Compatible with variable power scopes up to 40mm objective diameter

Field performance remains consistent across temperature extremes and heavy use. The steel construction handles the thermal expansion differences between base and receiver without loosening. Hunters report maintaining zero through hundreds of rounds and multiple seasons. The matte finish eliminates scope glint that can spook game at critical moments.

Technical Specs

• Material: Precision-machined steel with matte black finish
• Compatibility: Marlin 88, 89, 98 / Remington 12A, 121 / Stevens 416
• Mounting: Factory-drilled receiver holes (screws included)
• Slot configuration: Standard Weaver cross-slot pattern
• Profile height: Low-profile design for optimal scope positioning
• Weight: Approximately 2.5 ounces
• Country of origin: USA

This base represents the most cost-effective way to modernize classic rimfire rifles with quality optics. The Weaver name carries decades of proven performance in hunting camps and competitive shooting circuits worldwide.