Precision Twist Drill 5995803 Extra Length Drill Bit

Product Description

The PRECISION TWIST DRILL 5995803 is a 7/16-inch diameter extra length high speed steel drill bit engineered for deep-hole drilling in demanding shop and field applications. Built on the QC0860P series platform, it features a parabolic flute design that improves chip evacuation at depth and reduces heat buildup compared to standard spiral flutes. The 135-degree split-point tip is web-thinned and self-centering, eliminating the need for a center punch on most workpieces. Overall length is 8 inches with a 6-inch flute length, giving machinists and fabricators extended reach without sacrificing rigidity. The straight-cylindrical shank measures 7/16 inch in diameter with a 2-inch shank length, fitting standard drill chucks and collets. Finish is uncoated. Cutting direction is right hand.

This bit is suited for production and maintenance drilling in metal fabrication, manufacturing, and general industrial environments. Its extra length profile makes it particularly useful when standard-length bits cannot reach the bore location due to fixture depth, workpiece geometry, or bolt-boss configurations. The parabolic flute geometry and web-thinned point reduce thrust force, which is especially beneficial when drilling into interrupted cuts or multi-material stacks. Installation is performed by machinists, tool-and-die techs, and maintenance mechanics working with drill presses, CNC machining centers, or heavy-duty hand drills.

Key Features

• 7/16-inch (0.4375-inch) diameter, 8-inch overall length for extended reach drilling
• Parabolic flute profile accelerates chip removal and reduces heat at depth
• 135-degree split-point with web thinning for self-centering, low-thrust entry
• High speed steel construction rated for high-performance drilling across a broad material range
• Right-hand cutting direction with parallel web configuration
• ANSI-standard geometry; QC0860P series; 10xD flute-to-diameter ratio

Compatibility

Compatible workpiece materials include aluminum, aluminum alloy, brass, bronze, carbon steel, cast iron, copper, graphite, hardened steel, high strength bronze, magnesium, magnesium alloy, malleable iron, nickel, nickel alloy, reinforced plastic materials, stainless steel, steel, and cermet. Fits any drill chuck or collet accepting a 7/16-inch straight-cylindrical shank.

Installation Notes

Secure the shank fully in the chuck or collet before operation and verify runout with a dial indicator when tolerance is critical. Power down and de-energize the machine spindle before bit changes. Apply appropriate cutting fluid or coolant for the workpiece material to extend tool life, noting this bit does not support through-coolant delivery. Follow shop safety protocols and applicable ANSI B11 machine tool standards when operating drilling equipment.