Engineered for deep-hole precision and dependable performance, the Dormer Pramet A125 21/64 Inch x 310 mm HSS Straight Shank Extra Long Series Drill (BS 328) is the go-to choice when reach and rigidity matter. This drill combines a robust starting point with versatile material compatibility, delivering clean holes in a wide range of metals.

Why this drill stands out

• 118-degree conventional point: A strong, self-centering tip that starts quickly and resists wandering. The geometry is also easy to re-grind, helping you extend tool life between sharpenings.
• Steam oxide finish: Reduces friction and helps prevent workpiece material from sticking to the cutting edge, promoting smoother chip flow and longer edge life.
• Extra-long 310 mm length: Specifically designed for drilling very deep holes and applications where extended reach is essential—no need to swap tools mid-task.
• Premium HSS material: High-speed steel construction delivers strong performance across a variety of metals, including steel, aluminum, and stainless steel, while maintaining good edge retention.
• Straight shank design: Compatible with standard drill chucks and collets, providing consistent grip and accurate hole alignment on a range of machines.
• BS 328 compliance: Size and fit meet established standards for reliable interchangeability and predictable performance in professional shops.

Ideal uses and practical benefits

• Perfect for fabrication, maintenance, and repair tasks that require deep bore holes in long workpieces, frames, or assemblies where access is limited.
• Well-suited for drilling through mixed materials commonly found in machinery and automotive components, from steel to aluminum and stainless steel.
• In a production or workshop setting, this drill reduces tooling changes and downtime when deep-hole drilling is a frequent requirement.

Tips for best results

• Pair with an appropriate spindle speed and feed rate to optimize the 310 mm length—start with conservative speeds and adjust based on material and breakthrough feel.
• Utilize a steady lubrication or coolant to manage heat buildup and extend tool life, especially when working with stainless steel or alloys.
• Regularly inspect the cutting edges after re-sharpening to maintain the strong point and ensure consistent hole quality.