Top 10 5/16 Cobalt Drill Bit – Jobber Drill Bits

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BOSCH CO2147 5/16 In. x 4-1/2 In. Cobalt Drill Bit

BOSCH #ad - Available in jobber length, full shank. Rigid, thick web design adds stability to bit in tough applications. Best used for drilling into light-gauge metal, aluminum and ally steel, high-carbon steel, cast iron, stainless steel and titanium. Withstands high-temperature applications for extended periods of time up to 1, 100 degreeF. Surface hardened to penetrate tough abrasive materials.
BrandBOSCH #ad
ManufacturerBosch #ad
Height0 Inches
Length0 Inches
Width0 Inches
Part NumberCO2147

2. Hymnorq


Extremely Heat Resistant, Jobber Length and Straight Shank, Suitable for Repeated Drilling in Stainless Steel, Hymnorq 5/16 Inch Fractional Size M35 Cobalt Steel Twist Drill Bit Set of 5pcs

Hymnorq #ad - Cobalt steel - manufactured from m35 grade cobalt steel, with molybdenum and cobalt added to creates a hardened alloy, measuring Rockwell hardness up to 67, for much faster cutting and extra longer life span, with up to twelve times when compared with an average HSS drill bit.

Not for hardened steel / high carbon steel. Self centering - the 135°quick-cut pilot split points are self-centering and can penetrate quickly with less pressure. For metalworking - particularly successful in cutting through hard metalshardness less than HRC38° such as stainless steel and cast iron, although they can be used for softer materials like copper and aluminium, too. Try to adjust the RPM when it fails to penetrate. Manufactured to German DIN338 standard. The bits will not "walk" or "wander". 5pc set - the set includes 5pcs of 5/16” diameter m35 grade cobalt steel twist drill bits, packed in a plastic casefor easy storage and carrying.

In most cases, our customers would get a much better result with these tips. Straight shank allows for firmly holding and accurate centering, fit for standard drill chucks and regular round collet chucks. Downloadable user guide - we've summed up some tips of drilling metals, including a RPM chart for several common metals, based on our reviews and some articles on the internet. Welcome to download.
BrandHymnorq #ad
ManufacturerHymnorq #ad



Pack of 5 8mm, 5/16", HSS M35 Cobalt Twist Drill Bits

BEILI TOOLS #ad - High quality material. Reduce the processing cost per hole. High speed steel 5% Cobalt M35. The imperial size 5/16" is for reference, 5/16" equals to 7. 94mm. Real size is 7. 96mm, we rounding up 8mm. Please confirm the size before ordering. Drilling in tough metal, including heavy-duty abrasive alloy metal drilling on hardened steel. High efficiency In Drilling Metals, and Stainless Steel.
ManufacturerBEILI TOOLS #ad
Height5.59 Inches
Length2.05 Inches
Weight0.44 Pounds
Width0.55 Inches
Part NumberYTDB20178138



BOSCH CO2147B 5/16 In. x 4-1/2 In. Cobalt M42 Drill Bit

BOSCH #ad - High-heat resistant bits – withstand high-temperature applications for extended periods of time. Surface-hardened tip – penetrates tough abrasive materials. Enhanced m42 alloy material – contains 8% Cobalt alloy that delivers 10x life vs. Standard bits. Thick web-helix design – provides additional stability in tough applications. Cobalt m42 drill bit – provides upgraded m42 cobalt jobber-length bits designed for durability, high heat resistance and Hardened surface for stainless steel, titanium, cast iron, light-gauge metal and aluminum.
BrandBOSCH #ad
ManufacturerBosch #ad
Part NumberCO2147B
WarrantyProduct Defects Only

5. Drill Hulk


Pack of 6, 5/16-Inch Cobalt Steel M35 Jobber Length Twist Drill Bits for Hard Metal, Stainless Steel

Drill Hulk #ad - Can be repeatedly sharpened as needed: cobalt drill bit's hardness is uniform throughout the entire material, so that can be repeatedly sharpened without damaging the cutting edge allowing it to drill more than hss drill bits.

Include: 6 pieces of 5/16-inch cobalt drill bits with case. Made from high-speed steel and 5% cobalt: improve much higher heat resistance because of cobalt steel's high red hardness, provide strong durable performance compared to typical hss drill bits. Application: best used for drilling in hard metal, including stainless steel. Jobber length: 5/16-inch cutting diameter, 4-1/2-inch overall length, 135 degree split point, 3-3/16-inch flute length, 3-flat shank.
BrandDrill Hulk #ad
ManufacturerDrill Hulk Ltd #ad
Weight0.5 Pounds
Part NumberDHCO37

6. Dewalt


Industrial Cobalt, 5/16-Inch DWA1220, Pilot Point, DEWALT Drill Bit

Dewalt #ad - Heavy-duty cobalt of deWALT drill bits delivers 4 times more life than black oxide. Pilot point and split tip design of drill bits for wood, metal and plastic starts on contact and eliminates bit walking. Drill bit has maximum speed and life in stainless steel and other hard metals.
BrandDewalt #ad
ManufacturerDewalt #ad
Height6.73 Inches
Length1.87 Inches
Weight0.07 Pounds
Width0.33 Inches
Part NumberDWA1220

7. Hymnorq


135 Degree Split Point, Enhanced Hardness High Heat Resistance, 10X Life VS. Standard Bits, 8% Cobalt M42 Grade HSS-Co, for Stainless Steel Iron Hard Metals, Hymnorq 5/16 Inch Drill Bits 5pc Pack

Hymnorq #ad - Direct drilling can be done without prior centering or drilling of a pilot hole. M42 cobalt steel - constructed by m42 cobalt, a molybdenum series high-speed steel alloy with an additional 8 percent cobalt, measuring high hardness up to HRC67 - 69.

Much longer tool life means lower cost per hole drilled, although the price is higher. Widely used - ideal for metal manufacturing industries because of its superior red hardness as compared to more conventional high-speed steels. Centre punching is not necessary. Ground bits - the bits are fully ground for a smooth surface, reduction of chip friction, which allows even chip removal, extremely true running and precise round holes.

Lower cost per hole - higher durability than identically constructed HSS drill bits used under the same operating conditions. Designed for durability, cast iron, and hardened surface. Split point - 135-degree split point tip for self-centering and safe pilot hole drilling, even in slanting surfaces, in pipes and welds. Used for drilling various metals including stainless steel, light-gauge metal, high heat resistance, titanium, and aluminum.
BrandHymnorq #ad
ManufacturerHymnorq #ad
Weight0.27 Pounds



Pack of 5 5/16", LETON HSS M35 Cobalt Drill Bit Set, 8mm

LETON #ad - Using high-quality high-speed steel, through special treatment, steel, copper, processed iron, Aluminum and other metal materials. Twist drill bit with round shank, sharp spiral groove. Made of m35, namely cobalt High Speed Steel, for super abrasive resistance in tough metals. 100% brand new and High Quality. Durable, mainly used for bore machining.
BrandLETON #ad
ManufacturerBeili #ad

9. LudoPam


Stainless Steel, M35 HSS Twist Jobber Length for Hardened Metal, Cast Iron, Pack of 5, LudoPam 5/16 Inch Cobalt Drill Bit Set

LudoPam #ad - Include: 5 pieces of 5/16-Inch cobalt drill bits. Precise 135°split point & twist design: Prevent walking, clear chips and particles faster.

Particularly successful in cutting through hard metals such as stainless steel, hard plastics and woods, high temperature alloy, cast iron, titanium alloy, and also can be used for softer materials. Pay attention to speed, pressure and heat control during drilling. High quality material: 5% cobalt high speed Steel M35 provide extended tool life compared to ordinary drill bits. Durable, higher Heat & Abrasion Resistance. Professional & widely use: m35 cobalt hss is more suitable for hardened material.
BrandLudoPam #ad
ManufacturerLudoPam #ad
Part NumberM35-8-5P

10. Power Max


HSS Cobalt Drill Bits 5/16 in.x 4-1/2 in.Jobber Length M35 Twist Drill Steel Metal Iron-5Pcs

Power Max #ad - Split point quick-cutting points are self- centering and penetrate quickly with less pressure. Application: best used for drilling into light-gauge metal, high-carbon steel, aluminum and alloy steel, cast iron, stainless steel and titanium.

Surface treatment: the gold oxide ember finished surface treatment strongthen the hardness of drill bit body  to ensure the long drilling life and better drilling performance. Cobalt material: hssm35 cobalt steel is the premium material with high hardness and red hardness to enable long drilling life and fast drilling performance. Drill size: 5/16" diameter x 3-3/16"Flute Length x4-1/2"Overall Length. Split point angle 135 deg. No center punch is needed- the aggrevsive 135 deg. Will not "walk" or"wander".
BrandPower Max #ad
ManufacturerMAX-CRAFT #ad
Height0.32 Inches
Length5 Inches
Width3 Inches
Part NumberMPCO0516