2 1/2" Drill Bits | McMaster-Carr

When you need to drill dozens or even hundreds of holes, use a bit with replaceable carbide inserts. Once the cutting edges wear down, just change the inserts instead of sharpening or throwing the bit away. The holes in the bit channel coolant through the tool for more efficient chip evacuation. Also known as indexable drill bits.

Each drill bit requires two inserts—one on the inner cutting edge and one on the outer cutting edge. Replacement inserts are sold separately.

Drill Bits											Drill Bit Inserts			Replacement Insert Screws
				Shank			For Insert
Drill Bit Size	Decimal Size Equiv.	Overall Lg.	Max. Drilling Dp.	Type	Size	Drill Bit Point Type	Inner Inscribed Circle Dia.	Outer Inscribed Circle Dia.		Each	Pkg. Qty.		Pkg.		Each


	2 1/2"	2.5"	12 1/4"	7 1/2"	Round	1 1/2"	Carbide Insert	0.705"	0.732"	2769N41	000000000	10	2776N786	0000000	2780N16	00000

Carbide-Tipped Core Drill Bits for Masonry and Concrete

Remove a core of material with these hollow bits to make larger holes than fluted masonry bits. They're often used for installing pipe and conduit through brick and concrete. The carbide tip resists wear and heat to stay sharp.

Hex Shank for Rotary Only Drilling

The hex shape reduces the chance of the shank slipping in the chuck. Pair these bits with hand-held power drills and hammer drills set to rotary-only mode. Because they use rotary action only, they require more pressure to grind up material than other bits.

Pilot Drills—Cut a groove before drilling to make starting the hole easier.

	Drill Bits								Pilot Drills
	Drill Bit Size	Decimal Size Equiv.	Overall Lg.	Max. Drilling Dp.	Shank Size	Specs. Met		Each		Each
Uncoated


		2 1/2"	2.5"	12"	10"	1/2"	ANSI B212.15	2942A47	0000000	2942A69	000000

Drill Bit Extensions

		Each
18" Extension for 3/4" Hex Shank Size	2942A73	000000

Changeable-Size Carbide-Tipped Core Drill Bits for Masonry and Concrete

Instead of investing in multiple bits, change the bit body to drill a different-sized hole. These hollow bits remove a large core of material from concrete, brick, and masonry for installing pipe and conduit. The carbide tip resists wear and heat to stay sharp. Bits include a pilot drill to make starting holes easier.

SDS-Max Shank for Hammer and Rotary Drilling


	SDS-Max Shank

The slotted shank is compatible with SDS-Max-drive rotary hammers. These bits use simultaneous rotary and hammering action to penetrate material. Also known as percussion or impact bits.

	Max. Drilling Dp.	Specs. Met	Includes		Each
Uncoated





	Standard Point
	2 1/2"	2.5"	17"	12"	ANSI B212.15	Pilot Drill	3084A917	0000000

Accessories and Replacements for Drill Bits

Changeable Bit Bodies

Decimal Size Equiv.	Overall Lg.	Component	Specs. Met		Each


2 1/2"	2.5"	5"	Bit Body	ANSI B212.15	3084A46	0000000

Drill Bit Extensions, Replacement Shanks and Replacement Pilot Drills

		Each
6" Overall Length Extension	3084A59	000000
12" Overall Length Extension	3084A63	00000
18" Overall Length Extension	3084A64	000000
SDS-Max Shank	3084A121	00000
Pilot Drill for Changeable-Size Masonry Core Drill Bit	3084A58	00000

Spline Shank for Hammer and Rotary Drilling


	Spline Shank

The shank has 12 splines for use with a spline-drive rotary hammer, which rotate and hammers bits simultaneously to penetrate material. Also known as percussion or impact bits.

	Max. Drilling Dp.	Specs. Met	Includes		Each
Uncoated





	Standard Point
	2 1/2"	2.5"	17"	12"	ANSI B212.15	Pilot Drill	3084A817	0000000

Accessories and Replacements for Drill Bits

Changeable Bit Bodies

Decimal Size Equiv.	Overall Lg.	Component	Specs. Met		Each


2 1/2"	2.5"	5"	Bit Body	ANSI B212.15	3084A46	0000000

Drill Bit Extensions, Replacement Shanks and Replacement Pilot Drills

		Each
6" Overall Length Extension	3084A59	000000
12" Overall Length Extension	3084A63	00000
18" Overall Length Extension	3084A64	000000
Spline Shank	3084A132	00000
Pilot Drill for Changeable-Size Masonry Core Drill Bit	3084A58	00000

Rebar-Cutting Core Drill Bits for Concrete

Core out large holes in concrete, even if it's reinforced with rebar mesh. No need to switch bits, these have a diamond-coated edge that keeps on cutting and resists wear to stay sharp.

Threaded-Hub Shank for Rotary Only Drilling

Bits are designed for wet drilling on a drilling rig. To avoid damage to bits and tools, do not use for dry drilling or with portable drills or grinders.

	Max. Drilling Dp.	Shank Size	Thread Size	Bit ID		Each
Diamond Coated





	Standard Point
	2 1/2"	2.5"	15 1/2"	13"	2 1/2"	1 1/4"-7	2 1/4"	2872A56	0000000

Fast-Cutting Smooth-Finish Drill Bits for Wood

Round Shank

Standard Point

Not only do these bits bore holes faster than standard smooth-finish bits, they create less friction and heat buildup to last longer. The spurred teeth have a long life, but they're less effective at guiding the bit so cuts on angled and overlapping holes tend to be rougher. Also known as multispur bits.

	Max. Drilling Dp.	Shank Size	Drill Bit Point Type		Each
Uncoated





	Round Shank
	2 1/2"	2.5"	6"	4"	1/2"	Standard	2890A42	000000

Inserts for Carbide-Insert Drill Bits

Pair an inner and outer insert with a compatible drill bit body (sold separately) to drill a large number of holes with high precision. When the cutting edges dull, replace the carbide inserts instead of the entire bit.

Inner

										Each		Package
	For Drill Bit Size	For Mfr.	For Mfr. Series	IC Dia.	Thk.	Hole Dia.	Tip Radius	For Use On	Features		Each	Pkg. Qty.		Pkg.
Titanium Aluminum Nitride (TiAlN)-Coated Carbide


		2 1/4", 2 1/2"	Sandvik Coromant	CoroDrill 880	0.705"	7/32"	3/16"	1/32"	Steel, Hardened Steel, Tool Steel, Iron, Stainless Steel, Nickel, Titanium, Aluminum, Brass, Bronze, Fiberglass, Plastic	Chip Breakers	2776N28	000000	10	2776N786	0000000

Outer

										Each		Package
	For Drill Bit Size	For Mfr.	For Mfr. Series	IC Dia.	Thk.	Hole Dia.	Tip Radius	For Use On	Features		Each	Pkg. Qty.		Pkg.
Titanium Nitride (TiN)-Coated Carbide


		2 1/4", 2 1/2"	Sandvik Coromant	CoroDrill 880	0.732"	7/32"	3/16"	3/64"	Steel, Hardened Steel, Tool Steel, Iron, Stainless Steel, Nickel, Titanium, Aluminum, Brass, Bronze, Plastic	Chip Breakers	2776N29	000000	10	2776N945	0000000