Dormer Pramet A977 5.50 mm HSS‑E High Performance Multi-Application Extra Long Drill is engineered for engineers and machinists who demand precision, reach, and reliability in deep-hole work. This drill combines a refined geometry with rugged materials to deliver consistent performance across a wide range of substrates.

The 130° point is purposefully designed to be self‑centering, dramatically reducing the push force required to start a hole. That means cleaner starts, fewer wandering drills, and tighter hole concentricity—crucial when aligning components in assemblies or precision fixtures. The bright finish isn’t just cosmetic; it minimizes workpiece material adhesion to the cutting edge, promoting smoother penetration and easier chip control even in harder alloys.

Chips and heat are the enemies of long drill life, and the A977’s parabolic flute design is optimized to manage both. It enables efficient chip evacuation and stable cutting when drilling very deep holes in a single pass, reducing dwell time on each hole and lowering the risk of clogging or re-cutting chips that can mar hole quality.

Crafted from premium HSS‑E alloy, this drill bit is built to handle tough materials—from carbon steel to stainless steel and even certain aluminum grades. The result is dependable performance, longer tool life, and consistent hole quality across varied workpieces. The extra-long length provides the reach you need for deep cavities, deep-hole work in thick sections, or applications with limited access where standard-length bits fall short.

Standard DIN 1869 / 2 compliance ensures compatibility with common drill housings and accurate, repeatable performance in busy production environments. This isn’t a one-trick pony: it’s a versatile, durable tool designed for multi‑application drilling scenarios, giving you a reliable option when the job demands depth, straightness, and finish quality in a single pass.

Ideal applications
- Deep-hole drilling in steel, stainless steel, and aluminum components
- Automotive and aerospace assemblies requiring precise, long-reach holes
- Maintenance and fabrication tasks where access is limited and hole depth is critical

Practical tips for best results
- Use appropriate cutting speeds and feeds to match material type and depth; the self-centering point and flute design optimize performance when speeds are balanced with steady feeds.
- Lubricate or flood with coolant to maximize tool life and surface finish on harder alloys.
- Start with a light touch to let the 130° point seat cleanly, then gradually increase feed to maintain a smooth cutting action.