Dormer Pramet A125 13/64 Inch x 310 mm HSS ST STRAIGHT SHANK EXTRA LONG SERIES DRILL BS 328

The Dormer Pramet A125 13/64 Inch x 310 mm HSS ST Straight Shank Extra Long Series Drill (BS 328) is purpose-built for deep-hole metal work. With an overall length of 310 mm and a flute length of approximately 250 mm, this extra-long drill delivers the reach you need for drilling deep into thick workpieces without having to switch tools. It’s designed for demanding environments where depth and rigidity matter, offering a robust solution for long holes.

Key specifications at a glance

• Diameter: 13/64 inch
• Overall length: 310 mm; flute length ~250 mm
• Tip: 118° conventional point for strong starts and ease of re-grinding
• Shank: Straight, designed for compatibility with standard chucks and machine spindles
• Material/finish: High-speed steel (HSS) with a steam oxide finish to minimize sticking and improve edge lubrication
• Depth capability: recommended cutting depth up to 10xD for efficient deep-hole drilling
• Standards: BS 328-compliant geometry for reliable, repeatable performance

Why this A125 drill is a standout choice for metalworking

The 118-degree conventional point not only provides a strong, self-centering start but also reduces the effort required to break through material, making hole initiation smoother and more repeatable. When paired with the steam oxide finish, cutting edges stay cleaner longer, reducing built-up material on the tip and improving hole quality in a variety of metals.

Constructed from premium HSS, this drill excels across a broad range of materials—from steel and cast iron to aluminum and stainless steel. That versatility makes it a dependable all‑rounder for shops that encounter mixed-material assemblies or need a single tool that won’t slow down production when switching tasks. The straight shank ensures solid grip and predictable depth control in standard drill chucks and machines.

In line with BS 328 specifications, the A125 extra-long design is optimized for reach without compromising rigidity, giving you consistent hole quality even when the drill must traverse substantial material thickness. If your work requires drilling long, through-holes, this tool is engineered to keep feed steady and cuts clean from start to finish.

Practical use scenarios include automotive and machinery fabrication, steel fabrication kits, and any project needing deep drilling into thicker components where frequent bit changes would disrupt workflow. The combination of the long reach, robust HSS, and self-centering 118° point helps you complete deep-hole tasks more efficiently and with fewer tool changes.