Weaver #63B Top Mount 1-Piece Base Gloss Finish for Optics Mounting
- Type:
- Base - One Piece
- Firearm Make Fit:
- Marlin
- Finish-Color:
- Black - Gloss
- Mount Type:
- To Receiver
- Pieces:
- 1
- Model:
- Top Mount Base
- Material:
- Aluminum
- Rings Included:
- No
The Weaver #63B is a single-piece aluminum scope base engineered for shooters who want a rock-solid, no-fuss foundation for their optics. Built to handle modern and classic rifles alike, as well as shotguns and long-range handguns, this base delivers the kind of reliability that matters when you're behind the gun. The gloss finish resists corrosion while keeping a professional appearance, and the lightweight aluminum construction means you're not adding unnecessary heft to your rig.
Single-piece bases like the #63B are valued for their inherent rigidity—there's no gap between front and rear sections, which can translate to more consistent zero retention and less hassle during installation and maintenance. If you're setting up a rifle for hunting, the range, or any serious shooting discipline, a quality base is the foundation everything else depends on.
Keep in mind that bases are model-specific: the #63B is designed for certain rifle platforms. Use Weaver's fit guide to confirm compatibility with your firearm before ordering. Because this is a single base, you may need to order a matching rear base to complete your setup, depending on your gun and scope configuration.
Key Features
- One-piece aluminum construction for maximum rigidity
- Gloss finish for corrosion resistance
- Lightweight design
- Compatible with modern and vintage rifles, shotguns, and long-range handguns
- Engineered for consistent optics mounting
Specifications
| Product | Weaver #63B Top Mount Base |
| Material | Aluminum |
| Finish | Gloss |
| Configuration | Single-Piece Base |
Frequently Asked Questions
Will the Weaver #63B fit my rifle?
The #63B is designed for specific rifle models. Weaver publishes a compatibility guide to help you identify the correct base for your firearm. Check their fit chart before ordering to ensure proper compatibility.
Do I need to order two bases?
This is a single base. Depending on your rifle and scope setup, you may need to order a front and rear base pair. Some rifles use one-piece base sets (marked in Weaver's catalog), while others use two separate bases. Confirm your rifle's requirements before purchasing.
What's the difference between a one-piece and two-piece base?
A one-piece base like the #63B is a single machined unit with no seam between front and rear—it can offer increased rigidity and simplified installation. Two-piece bases are separate components that bolt together. The choice depends on your rifle's dovetail configuration and personal preference.

