Weaver Grand Slam S402 Two Piece Top Mount Base Review

First Thoughts on the Weaver Grand Slam S402 Two Piece Top Mount Base

The Weaver Grand Slam S402 Two Piece Top Mount Base is a crucial, often overlooked, component in any serious marksman’s setup. As a seasoned outdoor and tactical gear specialist, I’ve seen countless rifles undermined by inferior mounting systems. This base promises precision and reliability, qualities I demand in my gear.

My need for a solid mounting solution arose from consistent zeroing issues with a budget-friendly rimfire rifle I use for small game hunting. The factory-installed base simply couldn’t hold zero after a few trips into the brush. I was looking for a cost-effective, robust solution that wouldn’t break the bank but would provide rock-solid stability.

Upon unboxing the Weaver Grand Slam S402 Two Piece Top Mount Base, I immediately noticed the heft of the steel construction. The machining appeared clean and precise, a stark contrast to some of the cheaper aluminum bases I’ve encountered. The finish was a deep, matte black, suggesting durability and corrosion resistance.

Compared to generic aluminum bases and even some name-brand options, the Weaver base felt significantly more robust. I considered options from Leupold and Warne, but the price point of the Weaver made it an attractive option for this particular rifle. I ultimately chose it for its reputation for solid performance without the premium price tag.

My first impression was cautiously optimistic. The build quality seemed excellent for the price, but the real test would be how it performs under field conditions. The potential for a stable, reliable mount at this price point definitely piqued my interest.

Real-World Testing: Putting Weaver Grand Slam S402 Two Piece Top Mount Base to the Test

First Use Experience

My initial testing ground for the Weaver Grand Slam S402 Two Piece Top Mount Base was my local shooting range. I mounted the base onto my .22LR rifle, a Ruger 10/22, and attached a budget-friendly 3-9×40 scope. I wanted to see if the base could handle the vibrations from repeated firing.

The weather was moderately warm and dry, ideal for sighting in a rifle. Installation was straightforward, with the included screws fitting snugly into the receiver. After about 50 rounds, I checked the screws for any loosening; they remained firmly in place.

The rifle maintained its zero surprisingly well after the initial sight-in. I didn’t experience any significant shifts in point of impact, even after bumping the rifle around a bit to simulate field conditions. This was a promising start, suggesting the base was indeed providing a stable platform.

Extended Use & Reliability

After several months of use, including numerous trips into the woods for squirrel hunting, the Weaver Grand Slam S402 Two Piece Top Mount Base has proven its worth. The finish still looks new, despite the occasional brush with branches and mud. I regularly clean the rifle after each outing, paying special attention to the base, but maintenance is minimal.

There are no signs of wear and tear on the base itself. The screws remain tight, and the zero has remained consistent. I’ve noticed a significant improvement in my accuracy, especially at longer ranges, due to the stable scope mount.

Compared to my previous experiences with cheaper bases, this has been a night-and-day difference. Those bases would frequently loosen or shift, leading to frustrating range sessions and missed opportunities in the field. The Weaver Grand Slam S402 Two Piece Top Mount Base has exceeded my expectations for a base in this price range.

Breaking Down the Features of Weaver Grand Slam S402 Two Piece Top Mount Base

Specifications

The Weaver Grand Slam S402 Two Piece Top Mount Base is precision-built from steel for enhanced durability and a custom fit. It features a square-cut notch that mates seamlessly with the cross bolt found in Weaver top mount rings. The product also includes custom hardened fastening screws.

These specifications are crucial for maintaining consistent zero. Steel construction provides superior rigidity compared to aluminum, minimizing flex under recoil. The precise machining and tight tolerances ensure a secure and repeatable mount, while the hardened screws prevent stripping and loosening over time.

Performance & Functionality

The Weaver Grand Slam S402 Two Piece Top Mount Base performs its job admirably, providing a solid and reliable platform for mounting optics. Accuracy is significantly improved due to the stable connection between the scope and the rifle. It has shown excellent reliability even under moderate recoil and varying weather conditions.

The strength of the base is its simplicity and effectiveness. Its rugged design ensures a secure mount, while its straightforward installation makes it user-friendly. However, the absence of integrated recoil lugs might be a drawback for larger caliber rifles with significant recoil.

The base meets and, in some ways, exceeds expectations for a budget-friendly steel base. It provides a level of stability and reliability that surpasses many of its competitors in the same price range.

Design & Ergonomics

The design of the Weaver Grand Slam S402 Two Piece Top Mount Base is straightforward and functional. The steel construction and matte finish give it a robust and durable feel. The two-piece design allows for easy access to the rifle’s ejection port and makes it easier to clean.

Installation is simple, requiring only basic tools and a few minutes of time. The low profile design keeps the scope close to the bore, promoting better cheek weld and improved accuracy. There is no significant learning curve; even a novice shooter can easily install this base.

Durability & Maintenance

The steel construction of the Weaver Grand Slam S402 Two Piece Top Mount Base ensures a long lifespan. With proper care and maintenance, it should last for many years of reliable service. The finish is resistant to scratches and corrosion, adding to its durability.

Maintenance is minimal. Simply wiping down the base with a clean cloth and applying a light coat of oil will keep it in good condition. The screws should be checked periodically for tightness to ensure a secure mount.

Accessories and Customization Options

The Weaver Grand Slam S402 Two Piece Top Mount Base is designed to work seamlessly with Weaver top mount rings. It is also compatible with many other brands of rings that utilize the Weaver rail system. There are no included accessories beyond the base itself and the mounting screws.

While the base itself doesn’t offer any customization options, it provides a solid foundation for mounting various optics, including scopes, red dot sights, and holographic sights. Its compatibility with the Weaver rail system allows for a wide range of accessory options.

Pros and Cons of Weaver Grand Slam S402 Two Piece Top Mount Base