The Weaver #42 Top-Mount Scope Base (Weaver part no. 48042) is machined for the Mossberg 400 and Remington 10/11/12, giving these classic pump guns 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 of these guns, 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 a Mossberg 400 or Remington 10/11/12 for hunting or slug shooting.

Key Specifications

• Purpose-built to fit the Mossberg 400, matching the receiver’s factory-drilled screw pattern.
• Also fits the Remington Model 10, 11, and 12, sharing the same drilled hole pattern.
• Listed as a 1-piece base, so a single component bridges the full mounting area.
• Uses Weaver’s To Receiver mount style, bolting directly to the factory tapped holes.
• Finished in black gloss to match most blued receivers.
• Machined from aluminum for a lightweight, corrosion-resistant base.
• Requires Weaver-style rings to complete the mount.
• Ships with rings not included, so pair it with your own Weaver-style rings.
• Cross-references as Weaver Application #42 on the brand’s official fit chart.

Frequently Asked Questions

What guns does this base fit? It’s machined for the Mossberg 400 and Remington Model 10, 11, and 12, listed under Weaver’s Application #42.

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

Does it require any gunsmithing to install? No, it bolts directly to the factory screw holes on these receivers.

Buy the Weaver #42 Top-Mount Scope Base for Mossberg 400 and Remington 10/11/12

A slug gun that puts glass on target starts with a base machined to the receiver’s exact geometry, and this Weaver #42 bolts straight to a Mossberg 400 or Remington 10/11/12 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.