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Weaver
Overview
The Weaver Grand Slam S402 is a scope base designed to provide a mounting surface for optics. It is constructed from aluminum and finished in black. This component attaches directly to the receiver, offering a foundational interface for scope rings. GPP build data shows this scope base appearing in a range of general-purpose AR-15 builds. It is commonly paired with traditional scope rings and a variety of low-magnification LPVOs and fixed-power optics, often configured for general utility.
Pros
- +Black finish is the most common color option in the GPP catalog.
- +Aluminum construction provides a balance of weight and rigidity.
Trade-offs
- −This product uses a Scope Base mounting type, which is a mid-range option; most products in this category use a Scope Mount.
Specifications
Available Merchants(7)
Prices checked
Price Alert
Price and stock
Availability is good for the Weaver Base Grand Slam S402: it was in stock at one retailer or another nearly every day in September 2026, and today all 7 retailers we track have it in stock. The best price drifted down from $16.19 to $14.46 over September 2026 without a real sale. Buying today, the lowest price is $13.57 at BattleHawk Armory, which matches the best price we saw in September.
Prices checked · refreshed daily across 37 retailers
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