The Weaver #40A Top-Mount Scope Base (Weaver part no. 48040) is machined for the Remington 700, Ruger M77, and Weatherby Mark V, giving these bolt-action rifles a factory-tight platform for a riflescope. Weaver cuts the base from aluminum and finishes it in a black gloss that matches most factory blued receivers. Because it’s machined to the exact screw pattern shared across this fit list, it bolts straight to the factory holes with no drilling or gunsmithing needed. This is the correct base to start with if you’re mounting glass on any of these three bolt-action platforms.

Key Specifications

• Purpose-built to fit the Remington 700, matching the receiver’s factory-drilled screw pattern.
• Also fits the Ruger M77, sharing the same drilled hole pattern.
• Also fits the Weatherby Mark V, sharing the same drilled hole pattern.
• Built for bolt-action receivers on this fit list.
• Listed as a 1-piece base, so a single component bridges the full mounting area.
• Positioned as the rear base on the receiver for correct scope eye relief.
• Finished in black gloss to match most blued receivers.
• Machined from aluminum for a lightweight, corrosion-resistant base.
• Cross-references as Weaver Application #40A on the brand’s official fit chart.
• Ships at a featherlight 0.0313 lb, adding almost nothing to your order.

Frequently Asked Questions

What rifles does this base fit? The Remington 700, Ruger M77, and Weatherby Mark V, listed under Weaver’s Application #40A.

Are scope rings included? No, this is the base only; pair it with a set of Weaver-style rings to finish the mount.

Buy the Weaver #40A Top-Mount Scope Base for Remington 700, Ruger M77, and Weatherby Mark V

A base machined to the exact receiver pattern keeps a scope tracking true shot after shot, and this Weaver #40A bolts straight to a Remington 700, Ruger M77, or Weatherby Mark V with no modification. Order it from our Lubbock, Texas gun shop and it ships fast to your door, along with more scope bases and mounting hardware.