Bulk 5/16"-18 Carriage Bolts A307 Grade A Coarse HDG

Durable, Corrosion-Resistant Fasteners for Secure Connections in Challenging Environments

Elevate your woodworking, construction, and outdoor projects with our premium 5/16"-18 Carriage Bolts, crafted from A307 Grade A steel and Hot Dipped Galvanized (HDG) for enhanced corrosion resistance. These bolts offer dependable strength, making them ideal for applications where durability and reliability are crucial.

Carriage bolts feature a smooth, domed head with a square neck beneath. This design self-locks into a pre-drilled hole, preventing rotation as you tighten the nut. Perfect for wood-to-wood, wood-to-metal, and even some light metal-to-metal applications, carriage bolts are commonly used in fencing, decking, furniture assembly, and projects requiring tamper-resistant connections.

Undersized Options for HDG Fasteners

Certain bolt lengths may be undersized to compensate for the zinc coating added during the galvanizing process. The zinc layer slightly increases thread diameter, so starting with an undersized thread ensures that after galvanizing, the threads fit standard nuts and components properly. Refer to the variation details to see which lengths are undersized.

• Compensation for Zinc Buildup: Undersizing accounts for the zinc thickness, ensuring a correct post-galvanizing fit.
• Smooth Nut Installation: Undersized threads prevent overly tight fits after galvanizing, simplifying nut installation.
• Design Consideration: Specifying undersized HDG fasteners ensures proper functionality and ease of assembly in your project.

Key Benefits of Our HDG Carriage Bolts

• Corrosion Resistance: Hot Dipped Galvanizing provides excellent protection against rust and corrosion, ideal for outdoor and industrial environments.
• Self-Locking Square Neck: The square neck design keeps the bolt from spinning as the nut is tightened, ensuring a stable connection.
• Flush, Clean Appearance: The domed head sits flush with the surface, offering a neat, professional look.
• Easy Installation: Just tap the bolt into place and tighten the nut—no twisting of the bolt head required.
• Tamper-Resistant: The smooth head allows removal only from the nut side, increasing security.

Why Choose Our Bulk Carriage Bolts?

• Bulk Pricing: Ideal for contractors and large-scale projects, save with volume discounts.
• Wholesale Availability: Perfect for B2B customers requiring significant quantities.
• Quality Material: A307 Grade A steel with HDG coating ensures durability and corrosion resistance.
• Versatile Use: Suitable for woodworking, fencing, decking, furniture assembly, light construction, and more.

Product Specifications

• Diameter: 5/16"
• Thread Pitch: 18 TPI (Coarse Thread)
• Length: Measured from under the head to the end of the shank
• Head Style: Domed (Round) Head with Square Neck
• Material: A307 Grade A Steel
• Coating: Hot Dipped Galvanized (HDG) for enhanced corrosion resistance
• Undersized Options: Certain lengths may be undersized (see variation details) to ensure proper fit post-galvanizing
• Standards Compliance: Conforms to standard carriage bolt dimensions (ASME B18.5 or equivalent)

Ideal Applications

• Wooden Structures: Ideal for decking, fencing, walkways, and garden fixtures.
• Furniture and Woodworking: Ensures stable, flush connections and a neat finish.
• Outdoor Installations: Provides corrosion resistance for playground equipment, garden structures, and other exterior projects.
• Light Construction: Suitable for projects requiring secure, tamper-resistant fasteners.
• Industrial Applications: Suitable for environments exposed to moisture and corrosive agents.

Complementary Products

• Matching Nuts: (Add link to 5/16"-18 A307 Grade A HDG Nuts if available)
• Matching Washers: (Add link to 5/16"-18 A307 Grade A HDG Washers if available)

Build with Confidence Using Our Bulk Carriage Bolts

Choose our 5/16"-18 Carriage Bolts for secure, long-lasting connections in challenging environments. With bulk and wholesale pricing, Monster Bolts provides top-quality HDG fasteners—available in both standard and undersized thread options—to meet your project needs, backed by exceptional customer service.

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