Chicago-latrobe 57220 Jobber Drill Bit 5/16 in Hss

Product Description

The CHICAGO-LATROBE 57220 is a jobber-length drill bit designed for general-purpose drilling in a wide range of materials. Built from high speed steel with an oxide coating, this 5/16 inch diameter bit features a 118-degree split point for fast engagement and reduced walking on entry. The tapered web and web-thinned geometry lower thrust requirements and improve chip evacuation through the two spiral flutes. At 4.5 inches overall length with a 3.1875-inch flute length, the 57220 fits standard drill chucks and drill presses used daily in trade work. Licensed contractors, maintenance techs, and fabricators working in HVAC, plumbing, and electrical rough-in regularly reach for jobber bits in this size class.

The 57220 is suited for drilling into magnesium alloy as its primary rated workpiece material, and its general-purpose tool performance rating makes it a practical choice for mild steel, aluminum, and similar non-hardened metals encountered in mechanical and electrical trade applications. The straight-cylindrical shank with a 5/16 inch diameter seats securely in keyed or keyless chucks without slipping under normal feed loads. Right-hand spiral flutes clear chips efficiently without requiring coolant-through capability, keeping the setup simple on the bench or in the field.

Key Features

• 5/16 inch (0.3125 inch) diameter with tight tolerance of -0.0010 to 0.0000 inches for accurate hole sizing
• 118-degree split point reduces walking and lowers entry thrust compared to conventional points
• High speed steel construction with oxide finish for corrosion resistance and surface hardness
• Web-thinned, tapered web design improves chip flow and reduces heat buildup at the cutting edge
• Right-hand, two-flute regular spiral configuration for dependable chip evacuation in general metals
• Straight-cylindrical shank fits standard 3-jaw chucks on drill presses and hand drills

Compatibility

Designed as an OEM-style jobber-length replacement drill bit suitable for use in standard drill presses, hand drills, and drill drivers accepting a 5/16 inch straight-cylindrical shank within the Series 150K product line.

Installation Notes

Install and remove drill bits only with the drill unplugged or the power source locked out per OSHA lockout-tagout procedures. Secure the shank fully into the chuck and tighten all jaws evenly before drilling. Use appropriate work-holding fixtures to prevent workpiece movement, especially in metal drilling applications. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point shows visible damage.