Accupro 20399 Carbide Jobber Drill Bit 5/16 in 150 Deg Tin

Product Description

The ACCUPRO 20399 is a solid carbide jobber-length drill bit designed for precision hole-making in hard and abrasive materials. Ground to a 150-degree point angle with a standard point geometry, this bit cuts right-hand with three spiral flutes in a regular helix, providing efficient chip evacuation and stable cutting action. The titanium nitride (TiN) coating extends wear life and reduces friction at the cutting edge. At 3.75 inches overall length with a 1.875-inch flute length, it fits standard drill chucks via its straight cylindrical shank. Machinists, tool-and-die workers, and maintenance technicians working with stainless steel, hardened alloys, or cast iron reach for solid carbide tooling when high-speed steel falls short.

This bit is suited for CNC machining centers, drill presses, and manual machines in job shops, production floors, and MRO environments. The 5xD flute-to-diameter ratio and three-flute configuration make it particularly effective in short-chipping materials where heat buildup and chip packing are common failure points. No coolant-through capability is present, so external coolant or cutting fluid application is recommended when drilling at higher feeds and speeds in heat-sensitive workpieces. It conforms to ANSI specification designation standards for jobber-length drills.

Key Features

• Solid carbide construction for rigidity and heat resistance in hard materials
• TiN coating reduces friction and extends cutting edge life
• 150-degree point angle suited for harder, less ductile workpiece materials
• Three spiral flutes with regular helix for controlled chip evacuation
• Straight cylindrical shank fits standard drill chucks without adapters
• ANSI-compliant jobber-length geometry for consistent dimensional performance

Compatibility

Designed as an OEM-style replacement or direct tooling selection for applications requiring a 5/16-inch diameter solid carbide jobber drill bit with a straight cylindrical shank, compatible with any standard drill chuck accepting that shank diameter.

Installation Notes

Installation and use should be performed by qualified machinists or technicians familiar with cutting tool safety practices. Secure the shank fully in the chuck and verify runout before drilling. Solid carbide is brittle compared to high-speed steel and can fracture if subjected to side loads or interrupted cuts without adequate setup rigidity. Apply external cutting fluid when drilling materials that generate significant heat, as this bit does not support coolant-through delivery.