When choosing a high-speed steel (HSS) drill bit, you may come across labels such as M1, M2, or even M7. These designations often cause confusion-especially the letter "M" and the specific meaning behind numbers like M2. This guide explains what M2 HSS drill bits are, what the "M" stands for, whether "M2 drill bit" refers to a size, and how M2 compares to other grades such as M1.
What Is an M2 HSS Drill Bit?
An M2 HSS drill bit is a drill bit made from High-Speed Steel grade M2, the most widely used and most versatile HSS grade in the toolmaking industry.M2 6542 refers to the same material, M2 high-speed steel (HSS), with "6542" being its designation under the Chinese national standard. It is a common type of tool steel known for its excellent combination of hardness, wear resistance, toughness, and red hardness, making it suitable for tools like drills, taps, and reamers
Because of its balance between toughness and hardness, M2 is used for:
✔ Metal drilling
✔ Wood drilling
✔ Plastic drilling
✔ General-purpose industrial cutting tools
In the drill-bit market, when a product is labeled "HSS M2," it indicates the material grade-not the shape, size, or application.
What Does the "M" Stand for in Drill Bits?
The "M" does not mean metric, nor does it refer to the size of the drill bit.
Instead:
"M" stands for Molybdenum series
High-speed steels are generally categorized into two major families:
| Category | Alloying Basis | Example Grades |
|---|---|---|
| T-series | Tungsten-based | T1, T15 |
| M-series | Molybdenum-based | M1, M2, M7, M42… |
Molybdenum-series HSS (M-series) rose to popularity because they deliver similar performance to tungsten-based steels but are more cost-efficient and easier to manufacture.
What Size Is an M2 Drill Bit?
This is a common misconception.
"M2" refers only to the material.
The drill bit size depends on the design-you can have:
M2 1 mm drill bit
M2 3/8" drill bit
M2 step drill bit
M2 jobber-length drill bit
M2 extra-long drill bit
So the correct understanding is：
M2 is the steel grade. The size can be anything the manufacturer produces.
What Is the Difference Between HSS M1 and M2?
Both M1 and M2 belong to the molybdenum-based HSS family, but they are not equivalent.
Here's a simplified comparison：
| Property | HSS M1 | HSS M2 |
|---|---|---|
| Hardness | Medium | Higher |
| Red-hardness | Good | Better |
| Wear resistance | Moderate | Higher |
| Toughness | Slightly better than M2 | Good |
| Common use | Lightweight cutting tools, files | Drill bits, end mills, reamers, taps |
| Market usage | Low | Very high (industry standard) |
Final Summary
| Question | Quick Answer |
|---|---|
| What is an M2 HSS drill bit? | A drill bit made of M2 molybdenum-based high-speed steel. |
| What does M stand for? | "M" = molybdenum-series HSS (material category). |
| What size is an M2 drill bit? | Any size. "M2" is material, not dimension. |
| Difference between M1 and M2? | M2 has better hardness, wear resistance, and heat resistance-making it the preferred grade for drill bits. |
At Ceres Tools, we manufacture professional-grade M2 HSS drill bits-including jobber-length, reduced-shank, step bits, and custom geometries.
Our OEM/ODM service supports:
M2, M35, M42 HSS
Metric, fractional, letter & number sizes
Private labeling & packaging customization
Stable bulk production and global shipping
👉 Contact our engineering team to get samples or request a quotation today.
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