Best Reduced Shank Drill Bits for Drilling Stainless Steel (2026)

We selected bits based on documented cobalt content, reduced-shank compatibility with 1/2" chucks, customer ratings, and relative value across the category

This roundup covers reduced shank drill bits suited for drilling stainless steel, focusing on durability, shank compatibility, and heat-resistant cutting performance. Picks were chosen by evaluating material (cobalt grade), shank size compatibility for 1/2" chucks, user ratings, and overall value across documented product specs

Top Picks

  1. 1
    Drill America 57/64in Reduced Shank Cobalt Drill Bit

    Drill America 57/64in Reduced Shank Cobalt Drill Bit

    Drill America • ★ 4.0/5 • Budget

    Cobalt drill bit with 1/2in shank for harder metals. Improves performance with cobalt content and gold oxide surface. Some customers report variability in dullness and durability

    • cobalt enhanced performance for hard metals
    • versatile round shank for diverse toolholders
    • aerospace standard 907 compliance
    Check current price on Amazon →
  2. 2
    Drill America 29/32" cobalt drill bit, 1/2" shank

    Drill America 29/32" cobalt drill bit, 1/2" shank

    Drill America • ★ 3.9/5 • Budget

    Cobalt steel drill bit with round shank for versatile toolholding. Designed for harder metals with cobalt content; gold oxide surface indicates coating type. Customer insight notes mixed results on sharpness and durability

    • cobalt for hard metals
    • round shank compatibility
    • aerospace standard 907
    Check current price on Amazon →
  3. 3
  4. 4
    Drill America 15/16 in Reduced Shank Cobalt Drill Bit

    Drill America 15/16 in Reduced Shank Cobalt Drill Bit

    Drill America • ★ 3.9/5 • Budget

    Cobalt drill bit with 1/2 in round shank for use in various toolholding systems. Designed for drilling harder metals; features a gold oxide surface and counterclockwise chip evacuation. One customer note highlights varied sharpness and durability

    • cobalt for harder metals
    • round shank for versatile holders
    • aerospace-standard 907
    Check current price on Amazon →
  5. 5
  6. 6
    DWDCO cobalt reduced-shank drill bit, 1/2 in shank

    DWDCO cobalt reduced-shank drill bit, 1/2 in shank

    Drill America • ★ 3.7/5 • Mid-Range

    Cobalt drill bit with 1/2" round shank for versatile tooling. Improves performance when cutting harder metals; round shank supports varied toolholding. Some users report brittleness and wobble in use

    • cobalt for high-temp durability
    • round shank compatibility
    • aerospace-standard manufacture
    Check current price on Amazon →
  7. 7

Buying Guide

Choose the right alloy

Cobalt (often labeled M35/M42) retains hardness at high temperatures and is the preferred material for stainless-steel drilling

Match reduced shank to your chuck

Reduced shank bits let larger diameters fit 1/2" chucks; confirm the shank diameter and taper to ensure proper fit and grip

Look for coating and finish

Gold-oxide and similar coatings reduce galling and improve chip flow, extending bit life when cutting stainless

Check fractional diameters you need

Larger fractional sizes (e.g., 15/16"–63/64") are common in reduced shank sets; pick sizes that match your project requirements

Balance cost versus longevity

Cobalt reduced shank bits carry a higher upfront cost but typically offer longer life and better performance than high-speed steel in stainless