Dormer Pramet A125 11/16 Inch x 310 mm HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILL BS 328

Meet the Dormer Pramet A125 11/16" x 310 mm HSS Straight Shank Extra Long Drill BS 328 — a purpose-built solution for deep-hole drilling where reach, precision, and reliability matter. This drill bit is engineered to handle demanding metalworking tasks with a blend of toughness, accuracy, and ease of maintenance you can feel in every cut.

• 118° conventional point — delivers a strong starting bite with reduced wandering. The geometry is designed for clean entry into tough materials and is easy to re-sharpen when you need to restore the edge in-shop.
• Steam oxide finish — minimizes built-up edge and helps chips flow away from the cutting edge, reducing heat buildup and making deburring and cleaning simpler after the job is done.
• Extra Long length series — specifically designed for drilling very deep holes or reaching into recessed areas where standard-length bits can’t reach. You gain extended reach without compromising rigidity.
• Premium HSS material — high-speed steel provides robust performance across a range of metals, including steel, aluminum, and stainless steel, with reliable wear resistance and consistent hole quality.
• Straight shank — broad compatibility with most drill chucks and collet systems, offering stable performance and straightforward setup.
• Size and standard — 11/16" diameter with a 310 mm overall length, conforming to BS 328 for dependable interchangeability with compatible tooling and machinery.

Why this drill bit shines in real-world work

When you’re faced with long, straight bores in a production line or a DIY project that requires deep penetration, the A125 delivers consistent hole quality from start to finish. The extended reach keeps tolerances tight and reduces the need for secondary operations, while the 118° point minimizes runout and helps you maintain control at the entry. The versatile HSS core works across common metals, giving you a single tool that covers multiple materials without compromising performance.

Who benefits most

• Machinists and fabrication professionals needing deep-hole drilling in steel, aluminum, or stainless steel.
• Shop floors with variable machines (drill presses, manual machines, or CNC setups) that value a reliable straight-shank, long-reach bit.
• DIY enthusiasts tackling automotive, appliance, or metalworking projects where deep, accurate holes are essential.

Practical tips for optimal results

• Secure the workpiece and establish a pilot mark to guide the bit through dense materials.
• Use appropriate cutting fluid and moderate speeds to control heat, especially when drilling stainless steel.
• Maintain steady, even feed to maximize edge life and achieve true, straight holes.
• Retract occasionally to clear chips and inspect the cutting edge; re-sharpen when necessary to preserve accuracy.
• Pair with a compatible drill chuck or collet to ensure minimal runout and consistent performance across long bores.

Unlock deeper holes with confidence using the Dormer Pramet A125 Extra Long Drill — a precise, durable, and versatile choice for serious metalworkers who demand more from their drill bits.