DeWalt 1/8" x 3" Drill Bit Premium Percussion

Why I reached for this bit

Mounting electrical boxes on CMU, running Tapcon-style screws into a foundation wall, and pinning furring strips on old brick—those are the kinds of tasks that live and die by whether your masonry bit keeps cutting cleanly. On a recent retrofit, I ran a 3/16-inch DeWalt masonry bit in a cordless hammer drill for a full day of anchor holes. It’s sold in a 25-pack, which tells you who it’s aimed at: people who actually chew through masonry, not just nibble at it.

Design and build

The bit I used is a standard straight-shank masonry bit with a two-cutter carbide tip, a four-flute spiral, and three flats machined into the shank to help the chuck hold on. Overall length is 6 inches with a working length right around 4 inches, which covers most common anchor depths while leaving enough shank for the chuck to grip.

A few design notes stood out in hand:

• The carbide is broad across the nose for a two-cutter, offering good surface area on impact.
• The four-flute spiral is relatively open, which matters more than people realize—dust removal is drilling speed in masonry.
• The shank flats are cut cleanly and land where the jaws want to bite; they’re a small thing that solves a big annoyance: bit spin in the chuck under percussion.

It’s a straight-shank bit, not SDS. That’s worth highlighting up front for compatibility.

Setup and compatibility

In a standard 3-jaw chuck (I used both a keyed 1/2-inch and a keyless 1/2-inch hammer drill), the flats all but eliminate micro-slipping you sometimes get when the percussion rhythm peaks. That translates into fewer stops to re-tighten the chuck, which is more helpful than it sounds.

A few caveats:

• It isn’t an SDS or SDS-Plus shank; it doesn’t lock into rotary hammers that require those profiles. If you’re running an SDS hammer, use the corresponding SDS bit.
• It’s not a 1/4-inch hex shank, so it won’t clip into impact drivers or quick-change chucks without an adapter (and you shouldn’t be hammer-drilling with an impact driver anyway).
• The flats are present on the version I tested; check your exact variant if you need that feature specifically.

If your drill expects a standard cylindrical shank and has a hammer mode, you’re good.

Speed, tracking, and hole quality

On block and brick, this bit is fast. The two-cutter head bites eagerly and the bit tracks without skittering if you start square and let the hammer do the work. I found it helpful to pulse the trigger for the first second to establish a dimple, then lean into steady pressure. The bit centers nicely and resists walking, even on dense, glazed brick faces.

In poured concrete (cured, 3,000–4,000 PSI range), it was predictably slower but steady. The key advantage here is the four-flute geometry: dust exits the hole efficiently, so you can keep pressure consistent rather than stopping every few seconds to clear chips. You still want to back the bit out periodically on deeper holes, but I could routinely get through 1-3/4 inches of concrete with fewer interruptions than with comparable two-flute spirals.

Exit breakout on through-holes was moderate and controllable. Easing off pressure as you approach the back face reduces spalling; the bit responds well to that finesse. Hole diameters were consistent enough for concrete screws—my 1/4-inch anchors grabbed firmly without drilling oversize.

Durability and heat management

Two-cutter masonry tips are a compromise: they cut quickly, but they’re not as smooth or rebar-tolerant as four-cutter heads. Within that context, the carbide here held up well. I put the bit through several dozen anchor holes across CMU, brick, and slab. The edge dulled in the way masonry edges do (rounded shoulders more than chips), but it kept producing to-spec holes for concrete screws for the entire day.

A few lessons that helped longevity:

• Keep the drill in hammer mode; rotary-only makes heat and polishes the carbide instead of chipping aggregate.
• Moderate pressure works better than gorilla force. Let the percussion break aggregate; your job is to keep the bit fed.
• Every inch or so, back out to clear dust. The spiral does its job, but compacted fines still increase friction and heat if you let them.

Hitting rebar is a no-go for any two-cutter masonry bit. If you strike steel, stop. Either shift the hole or switch to a rebar-cutting bit designed for that abuse.

Accuracy and repeatability

For Tapcon-style screws, consistency is everything. Too small and you snap screws; too big and you get pull-out. Across the day, holes landed in the Goldilocks zone for 1/4-inch screws, with depth repeatable using a simple tape flag on the shank. I checked diameter with a pin gauge once the bit had a few dozen holes on it—the wear had not oversize the hole beyond what the anchor’s thread-forming could tolerate.

One pleasant surprise: the bit starts surprisingly clean in glaze and old mortar joints. If you’ve fought the “ice rink” effect on smooth surfaces, this one—combined with a steady hand—doesn’t wander as much as some budget masonry bits.

Where it shines, and where it doesn’t

Strengths:
- Debris evacuation is better than average for a straight-shank masonry bit. That directly translates to faster drilling and less heat.
- The shank flats work. If you’ve ever blue’d a round shank from spin in the chuck, you’ll appreciate this.
- Tip design balances speed and life well for a two-cutter. It’s set up for the kind of repetitive anchor hole work that justifies a 25-pack.

Limitations:
- Not for SDS hammers. If your primary masonry tool is an SDS-Plus rotary hammer, use SDS bits. They drill smoother, straighter, and handle rebar encounters better in many cases.
- Two-cutter heads can chatter in very hard aggregate and will chip if you force through steel. That’s physics, not a flaw, but it’s worth remembering.
- The bulk pack makes sense for trades; casual users who only need a few holes might prefer buying singles in the same size.

Tips for best results

• Use hammer mode, mid-to-high speed, and steady pressure. Listen for the percussion cadence; if it slows, back out and clear dust.
• Mark depth with tape or use a stop. Overdrilling wastes time and shortens bit life.
• Vacuum the hole before anchoring. Dust left in the hole kills holding power more than a few thousandths of diameter ever will.
• For slick brick or tile-faced block, start at a slight angle to scratch a bite, then square up as soon as the bit seats.
• If you’ve got a dozen or more holes, rotate two bits. Alternating lets each cool and usually yields more total holes per bit.

Value

A 25-pack of 3/16-inch masonry bits isn’t for everyone, but if you’re hanging strut, mounting racks, or doing regular service work, the math checks out. The performance is consistent across the pack, and you won’t find yourself babying a single precious bit that you can’t afford to chip. For crews, the flats reduce downtime from chuck slip, and the four-flute spiral keeps drilling productive.

If you only need to set a couple of anchors, buy a single bit. For anyone else, the cost-per-hole on this pack is easy to justify.

Final thoughts and recommendation

After a full day of anchor setting across concrete, block, and brick, this DeWalt masonry bit did exactly what I want a straight-shank percussion bit to do: start cleanly, clear dust fast, hold diameter, and stay put in the chuck. It’s not a four-cutter SDS solution for heavy rotary hammers, and it won’t forgive a collision with rebar, but within its lane—hammer drilling with a standard 3-jaw chuck—it’s a dependable workhorse.

I recommend it for pros and serious DIYers who need reliable, repeatable 3/16-inch holes for concrete screws and similar anchors, especially if you value the convenience of a bulk pack. Just confirm your drill uses a standard chuck (not SDS or quick-change hex), run it in hammer mode, and let the bit do the work.