This AlCrN-coated 5 16 drill bit is engineered for high-performance drilling in demanding metalworking applications. Designed with internal coolant holes, it ensures efficient heat dissipation and chip evacuation, even during deep-hole and high-speed machining.
The advanced AlCrN coating provides exceptional hardness, oxidation resistance, and thermal stability, making this 5 16 drill bit for metal ideal for machining steel, stainless steel, and hardened steel materials. Compared with standard uncoated drills, the AlCrN-coated surface significantly reduces friction, extends tool life, and maintains consistent hole quality.
Manufactured with precision CNC grinding, the 5 16 drill bit size offers excellent dimensional accuracy and cutting edge stability. Both standard and long 5 16 drill bit options are available to meet different depth and application requirements. Metric and inch compatibility allows seamless integration into global machining operations.
3D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB310020 | 5/16 | 7.94 | 41 | 8 | 79 |
5D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB510020 | 5/16 | 7.94 | 53 | 8 | 91 |
Grade HN40 is made from submicron WC powder, some speclal additlves added to optimize theproperties with good combination of hardness and toughness.
Its suitable for making drills and miling tools for machining stainless steel, tool steel and heat-resistingalloys.
| Grade | Cobalt content % | Grain size | Density g/cm³ | Hardness HRA | Hardness HV30 | MPa Transverse rupture strength | MPa ·m1/2 Fracture toughness MPa ·m1/2 |
|---|---|---|---|---|---|---|---|
| HN40 | 10 | 0.8 | 14.45 | 91.8 | 1,580 | 3,600 | 11.8 |
| Scientific name | Composition | Physical properties | Features | Typical applications |
|---|---|---|---|---|
| ALCRN | Al: 18–32% Cr: 10–25% N: 45–57% | Hardness: 2800–3200 HV (≈30–32 GPa) Thickness: 1–5 μm (typically 3–4 μm in applications) Oxidation temperature: 1000–1100°C (short-term up to 1100°C) Deposition temperature: ＜500°C (suitable for HSS and carbide substrates) | Red hardness: maintains hardness even at 1100°C, better than TiAlN (whose hardness drops above about 900°C). Adhesion: critical load up to 40 N (with optimized process). Wear resistance: suitable for high-speed cutting and dry machining, especially effective on stainless steels and alloy steels. | Cutting tools: end mills, gear cutters, drills (e.g. Balinit Alcorna series). Moulds: aluminium die-casting moulds, stamping tools. Industrial parts: piston rings, high-temperature wear-resistant parts (combined with suitable interlayer design). |
Our 5 16 Drill Bit drawings clearly show key 5 16 Drill Bit dimensions such as diameter, radius, flute length and overall length. This helps you confirm the right 5 16 Drill Bit sizes for your CNC setup and machining depth before ordering.
The 5 16 drill bit size is 5/16 inch in diameter, which equals 0.3125 inch. In metric units, the 5 16 drill bit in mm is 7.94 mm. This precise conversion is important for CNC machining and applications requiring tight tolerances.
A 5 16 drill bit for metal is suitable for drilling:
Carbon steel
Stainless steel
Alloy steel
Aluminum and non-ferrous metals
With advanced coatings such as AlCrN, a 5 16 drill bit for hardened steel can also perform reliably under high-temperature and high-load condition
The 5 16 drill bit tap size is often misunderstood. A 5/16 drill bit is generally not used as a tap drill for 5/16 threads.
For example:
5/16-18 UNC → Letter F drill (6.53 mm)
5/16-24 UNF → 17/64 inch (6.75 mm)
The 5 16 drill bit is mainly used for clearance holes rather than tapping preparation.
Yes. We can produce non-standard tools according to your drawings, samples or machining requirements (material, coating, size, tolerance and application). Our engineers will evaluate and provide a quotation and lead time.
For serious buyers and distributors, we can offer free standard samples if in stock. Usually you only need to cover the freight cost. For customized tools, a sample fee may apply, which can be refunded or deducted in bulk orders.
Yes.
Regional or customer protection based on sales targets, avoiding price wars among our partners.
Catalogs, brochures, product photos, technical data sheets, online materials.
For key partners, joint promotion, exhibitions and digital marketing support.
Safety stock for fast-moving items and forecast-based production.
Priority production and regular shipments to reduce stock-out risk.
Clear quality warranty policy, quick response to claims.
Replacement, credit or other solutions after confirmation of issues.
Tool selection and cutting parameter advice.
Problem analysis for different materials and machines.
Online training, documents, and when possible, on-site support for key accounts.
This AlCrN-coated 5 16 drill bit without coolant holes is designed for stable and cost-effective drilling in a wide range of metal machining applications. Featuring a solid carbide body and precision-ground cutting edges, this tool delivers reliable performance in conventional and CNC drilling operations where external coolant or dry machining is preferred.
The advanced AlCrN coating enhances surface hardness and oxidation resistance, allowing the 5 16 drill bit for metal to operate efficiently under high cutting temperatures. This makes it suitable for drilling steel, stainless steel, alloy steel, and selected hardened steel materials, while maintaining consistent hole accuracy and extended tool life.
With an exact 5 16 drill bit size (7.94 mm), this drill offers excellent dimensional control and repeatability. Compared to drills with internal coolant holes, the solid construction provides higher rigidity, making it an ideal choice for shallow to medium-depth holes and applications requiring improved vibration stability. Standard and long 5 16 drill bit options are available to meet different machining requirements.
3D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB301020 | 5/16 | 7.94 | 41 | 8 | 79 |
5D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB501020 | 5/16 | 7.94 | 53 | 8 | 91 |
Grade HN40 is made from submicron WC powder, some speclal additlves added to optimize theproperties with good combination of hardness and toughness.
Its suitable for making drills and miling tools for machining stainless steel, tool steel and heat-resistingalloys.
| Grade | Cobalt content % | Grain size | Density g/cm³ | Hardness HRA | Hardness HV30 | MPa Transverse rupture strength | MPa ·m1/2 Fracture toughness MPa ·m1/2 |
|---|---|---|---|---|---|---|---|
| HN40 | 10 | 0.8 | 14.45 | 91.8 | 1,580 | 3,600 | 11.8 |
| Scientific name | Composition | Physical properties | Features | Typical applications |
|---|---|---|---|---|
| TiXCo3 | Advanced nanocomposite multilayer PVD coating based on Ti, Al, Cr and Si; usually built with a TiN or CrTiN adhesion layer, an AlTi(Si)N core and an extremely hard TiSiN nano-composite top layer. Copper-coloured coating designed specifically for hard-machining tools such as solid carbide drills. | Nano-hardness: 42–44 GPa (≈4300–4500 HV). Coefficient of friction: ~0.4 (PoD test, room temperature, 50 % humidity). Coating thickness: typically 1–4 µm. Maximum service temperature up to about 1,000–1,100 °C, giving excellent thermal stability and oxidation resistance for high-speed drilling in hard materials. | Copper appearance; delivers very high surface quality of the hole and extremely high wear resistance. Our hardest nanocomposite coating, optimized for hard machining and finishing operations in drilling, milling and reaming at very high cutting speeds. Suitable for dry or near-dry machining and for difficult-to-cut, abrasive alloys where long, stable tool life is required. | Recommended workpiece materials: hardened steels (up to ~60–64 HRC), stainless steels, tool steels, nickel-based superalloys, cast irons and other hard or abrasive metals. Typical application fields for drills: high-precision deep-hole and high-speed production drilling of dies and moulds, power-train and transmission components, aerospace turbine and structural parts, and other hard-machining operations demanding tight tolerances and excellent hole finish. |
Our 5 16 Drill Bit drawings clearly show key 5 16 Drill Bit dimensions such as diameter, radius, flute length and overall length. This helps you confirm the right 5 16 Drill Bit sizes for your CNC setup and machining depth before ordering.
The 5 16 drill bit size is 5/16 inch in diameter, which equals 0.3125 inch. In metric units, the 5 16 drill bit in mm is 7.94 mm. This precise conversion is important for CNC machining and applications requiring tight tolerances.
A 5 16 drill bit for metal is suitable for drilling:
Carbon steel
Stainless steel
Alloy steel
Aluminum and non-ferrous metals
With advanced coatings such as AlCrN, a 5 16 drill bit for hardened steel can also perform reliably under high-temperature and high-load condition
The 5 16 drill bit tap size is often misunderstood. A 5/16 drill bit is generally not used as a tap drill for 5/16 threads.
For example:
5/16-18 UNC → Letter F drill (6.53 mm)
5/16-24 UNF → 17/64 inch (6.75 mm)
The 5 16 drill bit is mainly used for clearance holes rather than tapping preparation.
Yes. We can produce non-standard tools according to your drawings, samples or machining requirements (material, coating, size, tolerance and application). Our engineers will evaluate and provide a quotation and lead time.
For serious buyers and distributors, we can offer free standard samples if in stock. Usually you only need to cover the freight cost. For customized tools, a sample fee may apply, which can be refunded or deducted in bulk orders.
Yes.
Regional or customer protection based on sales targets, avoiding price wars among our partners.
Catalogs, brochures, product photos, technical data sheets, online materials.
For key partners, joint promotion, exhibitions and digital marketing support.
Safety stock for fast-moving items and forecast-based production.
Priority production and regular shipments to reduce stock-out risk.
Clear quality warranty policy, quick response to claims.
Replacement, credit or other solutions after confirmation of issues.
Tool selection and cutting parameter advice.
Problem analysis for different materials and machines.
Online training, documents, and when possible, on-site support for key accounts.
The 5 16 drill bit is widely used in CNC machining, metal fabrication, and industrial manufacturing for its balanced size and excellent cutting stability. With an accurate 5 16 drill bit size, it is suitable for drilling steel, stainless steel, aluminum, and alloy materials across a broad range of applications.
Whether used as a standard or long 5 16 drill bit, this tool performs reliably in through holes and blind holes. Compared with smaller sizes, the 5 16 drill bit for metal offers improved rigidity and chip evacuation, making it a practical choice for medium to heavy-duty drilling operations in workshops and production lines.
Each 5 16 drill bit is manufactured with precision CNC grinding to ensure consistent diameter accuracy and stable cutting performance. The advanced AlCrN coating significantly enhances wear resistance and thermal stability, allowing the drill to maintain performance under high-speed and high-load conditions.
Designed for demanding environments, the 5 16 drill bit for hardened steel delivers smooth cutting action and extended tool life. For users comparing sizes, such as 5 16 drill bit vs 1/4, the 5/16 size provides greater strength and improved hole quality, making it ideal for professional metalworking applications where precision and durability are essential.
We Are Commited To Providing High-Quality, Customized solutions At An Affordable price While Also Prioritizing sustainability And ExcellentCustomer Service, These Qualities Make Us A Great choice For Your 5 16 Drill Bit Needs
We Only Use unground tungsten carbide rods with HlP sintering and 100% virgin material. Our grade includes lsO K05 to K40, frommachining carbon steel to aluminium, non-ferrous metals andtitanium or we develop grade for your applications.
As a HNCarbide customer, you can enjoy five-axis high-precisiongrinding machines from Australia’s ANCA or Germany’s Walter. Themodern workshop with constant temperature and humidity ensuresthe accuracy of each 5 16 Drill Bit.
Each of your tungsten 5 16 Drill Bit will be sandblasted to effectively remove burrs and improve the finish.
All HNCarbide’s 5 16 Drill Bit will be monitored on WALTER HELICHEEK and ZOLLER GENlUS 3 to ensure that every dimension is qualified. We arecommitted to controlling the tolerance within 3 UM.
At HNCarbide, every shipment is meticulously packaged to ensure your tools arrive intact.
Each HNCarbide’s 5 16 Drill Bit is individually placed in a shock-resistant protective case, labeled with complete specifications, and sealed in moisture-proof packaging material before being boxed.
Large-volume orders are reinforced with double-wall cardboard boxes or wooden crates to maximize safety during international shipping.
We collaborate with reliable logistics partners to ensure goods are delivered quickly and securely to their destination via air freight, sea freight, or express courier.
The 5 16 drill bit size is 5/16 inch in diameter, which equals 0.3125 inch. In metric units, the 5 16 drill bit in mm is 7.94 mm. This precise conversion is important for CNC machining and applications requiring tight tolerances.
A 5 16 drill bit for metal is suitable for drilling:
Carbon steel
Stainless steel
Alloy steel
Aluminum and non-ferrous metals
With advanced coatings such as AlCrN, a 5 16 drill bit for hardened steel can also perform reliably under high-temperature and high-load condition
The 5 16 drill bit tap size is often misunderstood. A 5/16 drill bit is generally not used as a tap drill for 5/16 threads.
For example:
5/16-18 UNC → Letter F drill (6.53 mm)
5/16-24 UNF → 17/64 inch (6.75 mm)
The 5 16 drill bit is mainly used for clearance holes rather than tapping preparation.
Yes. We can produce non-standard tools according to your drawings, samples or machining requirements (material, coating, size, tolerance and application). Our engineers will evaluate and provide a quotation and lead time.
For serious buyers and distributors, we can offer free standard samples if in stock. Usually you only need to cover the freight cost. For customized tools, a sample fee may apply, which can be refunded or deducted in bulk orders.
Yes.
Regional or customer protection based on sales targets, avoiding price wars among our partners.
Catalogs, brochures, product photos, technical data sheets, online materials.
For key partners, joint promotion, exhibitions and digital marketing support.
Safety stock for fast-moving items and forecast-based production.
Priority production and regular shipments to reduce stock-out risk.
Clear quality warranty policy, quick response to claims.
Replacement, credit or other solutions after confirmation of issues.
Tool selection and cutting parameter advice.
Problem analysis for different materials and machines.
Online training, documents, and when possible, on-site support for key accounts.
The 5 16 drill bit is a widely used fractional drill size in industrial machining and metalworking. Its balanced diameter provides a strong combination of rigidity, cutting efficiency, and versatility, making it suitable for a wide range of drilling applications. This article answers the most common technical questions about the 5 16 drill bit, including size conversion, material suitability, comparisons with nearby sizes, and practical selection guidance.
The 5 16 drill bit size is based on the imperial fractional system.
Diameter: 5/16 inch
Decimal equivalent: 0.3125 inch
5 16 drill bit in mm: 7.94 mm
When converting from imperial to metric, the 5 16 drill bit to mm value is essential for CNC programming and engineering drawings. Even small deviations can affect hole tolerance, especially in precision metal components.
Although often compared, an 8mm 5 16 drill bit substitute is not dimensionally identical.
5/16 inch = 7.94 mm
8 mm drill bit = 8.00 mm
The difference of 0.06 mm may seem minor, but it can cause tolerance issues in tight-fit assemblies or threaded applications. For accurate machining, the correct 5 16 drill bit size should always be used instead of metric substitutes.
A 5 16 drill bit for metal is commonly applied in:
Carbon steel
Stainless steel
Alloy steel
Aluminum and non-ferrous metals
With appropriate tool material and coating, a 5 16 drill bit for hardened steel can also be used effectively. Coatings such as AlCrN improve heat resistance and wear performance, making the drill suitable for high-speed CNC machining.
A standard 5 16 drill bit is sufficient for most general drilling operations. However, a long 5 16 drill bit is required when hole depth exceeds standard flute length.
Long drills are typically used for:
Deep-hole machining
Mold and die components
Structural or thick metal parts
When using longer tools, proper spindle alignment and controlled feed rates are critical to prevent deflection and tool breakage.
Many machinists ask about 5 16 drill bit tap size, but the answer depends on the thread specification.
For common 5/16 threads:
5/16-18 UNC tap → recommended drill size: Letter F (6.53 mm)
5/16-24 UNF tap → recommended drill size: 17/64 inch (6.75 mm)
This means a 5 16 drill bit is generally used for clearance holes, not as a tap drill for 5/16 threads.
The comparison of 5 16 drill bit vs 1 4 is common in metal machining.
1/4 drill bit: 6.35 mm
5 16 drill bit: 7.94 mm
The larger diameter of the 5/16 drill provides:
Greater rigidity
Reduced vibration
Improved performance in harder materials
For applications requiring higher strength and stability, the 5 16 drill bit is the preferred option.
When comparing 3 16 vs 5 16 drill bit, the difference lies mainly in application scope.
3/16 drill bit: light-duty and thin materials
5/16 drill bit: medium to heavy-duty metal machining
The larger cutting diameter allows the 5 16 drill bit to handle higher feed rates and maintain longer tool life under demanding conditions.
The 7 32 vs 5 16 drill bit size comparison highlights the significant difference between these fractional tools.
7/32 inch: ≈ 5.56 mm
5/16 inch: ≈ 7.94 mm
Although both are imperial sizes, they serve very different machining requirements. The 5 16 drill bit is used when larger hole diameters and stronger cutting performance are required.
When choosing a 5 16 drill bit, consider the following technical factors:
Workpiece material
Tool material (HSS, solid carbide)
Coating type (AlCrN, TiAlN, uncoated)
Cooling method (with or without coolant holes)
Required hole depth
For CNC machining and high-volume production, coated carbide drills provide superior consistency and durability.
The 5 16 drill bit offers an excellent balance between strength, precision, and versatility. Its well-defined size, compatibility with metal materials, and adaptability to both standard and long drilling applications make it a reliable choice in industrial machining. By understanding its size, comparisons, and proper usage, manufacturers can achieve more efficient and accurate drilling results.
Before you go, please note that we offer the most up-to-date industry research reports and the most comprehensive product catalogs, so please contact us if you are interested!
Before you go, please note that we offer the most up-to-date industry research reports and the most comprehensive product catalogs, so please contact us if you are interested!
