About 10 years ago, I bought a 1/2-inch hammer drill. It
dependably drilled anchor holes in tile, mortar, block, and
— usually — concrete. It also doubled as a regular
two-speed drill. But the tool struggled with large bits and had
a hard time with concrete that contained a lot of heavy
Last year, I had the opportunity to test seven hammer
drill-sized pistol-grip rotary hammers. For me, they took
concrete and masonry drilling to an entirely new level. My
decade-old hammer drill? I retired it from drilling
Over the course of 12 weeks, I ran the seven pistol-grip rotary
hammers in this group through a gauntlet of concrete and
masonry drilling tests both on the job site and in a controlled
environment — a Department of Transportation facility
where I could drill and chip old highway barriers made of
concrete with a known consistency. I tested the Bosch 11250VSR,
DeWalt D25103K, Hilti TE 2-M, Hitachi DH 24PC2, Makita HR2450F,
Metabo UHE 28 Multi, and Milwaukee 5383-21. All hammers use SDS
(slotted drive system) Plus bits (Hilti calls them TE-C
First, I conducted timed tests using new bits in each tool to
evaluate speed, power, and vibration. Next, I addressed
balance, grip, and triggering. Finally, I took a close look at
the bit holders, depth stops, and clutches. For each tool, I
evaluated the owner's manual, toolbox, and multiuse features.
The DeWalt, Hitachi, Makita, and Metabo have a chipping
function, which I tested for power and performance with
different bits. In the end, though, the ability to drill holes
quickly — with power to spare — influenced my
recommendations the most.
Power, Speed, and Vibration
I expect manufacturer specifications to be a solid indicator of
performance, but some of the specifications told me little
about how well these tools would perform when drilling
concrete. Amp draw, rpm, blows per minute, and even impact
energy failed to correlate closely enough with my test results
to make them accurate predictors of performance.
The specs do include one very useful number, the capacity
rating, which refers to the largest-diameter solid bit that the
manufacturer recommends using in concrete. (Most of these
tools, of course, will accept larger sizes than they are rated
for — SDS-Plus bits go up to 11/4 inches in diameter.)
The capacity rating is important because it tells you that if
you drill a lot of holes larger than that size, you will
shorten the life of the tool. If you are constantly drilling at
maximum capacity, the tool is probably too small. Ideally, you
should own a rotary hammer that is rated for a slightly larger
hole than you usually drill. You wouldn't want it to be rated
much higher, because you'd be using a bigger, heavier tool than
A rubber-padded grip and a large,
easy-to-activate trigger make the Hilti the most comfortable to
Power and speed. I used
brand-new 1/2-inch bits to drill uniform 3,000-psi concrete
— an old DOT highway barrier — containing aggregate
of up to 1 1/2 inches. This test material ensured reliable
content made to strict government specifications.
Manufacturers say the best way to get effective results with a
rotary hammer is to let the weight of the tool do the work,
rather than pushing it too hard. That is generally true.
Nevertheless, I see some guys pushing a tool to the limit, so I
tested the hammers not only with recommended pressures, but
also with hard and extreme pressures.
I explored drilling power through three separate tests. First,
I applied what I call a medium or recommended force to each
tool. I drilled four horizontal holes, 4 inches deep, timing
and averaging the results. I then drilled four more holes with
each tool, using what I consider a higher than recommended
force. When none of the tools bogged out with higher pressure,
I really pushed them to their limits by drilling one hole each
with as much force as I could. It's important to note that I
don't have a test lab with specialized equipment, but the times
in the chart are as accurate as could be recorded in the field
and reflect job-site conditions.
While pushing a tool hard all day is neither recommended by
manufacturers nor realistic for users, my results indicate that
the harder I pushed, the faster most of them went. However,
this is not a measure of durability. I couldn't test whether a
tool would last very long being pushed hard day in and day out.
DeWalt says its tool, which finished in the middle of the pack
in the speed test, is specifically designed for high-pressure
work, not speed. The company's research indicates that because
users overuse the tool, this design increases durability.
Vibration. For rotary
hammers, vibration is surprisingly isolated by the way the
hammer mechanism operates. Unlike a hammer drill's system of
two serrated discs rotating against each other — actually
a vibration-causing mechanism — the rotary hammer's
impact comes from pneumatic force. A piston on one end of a
cylinder compresses air, which slides a striking hammer at the
other end into the back of the bit, limiting vibration in the
tool body. All the tools operated comfortably except
Milwaukee's. It vibrated the most and was uncomfortable to
operate, especially with larger bits.
Balance, Grip, and Triggering
Each tool was well balanced and easy to maneuver for
straight-on or overhead work. If I had to nitpick, I'd say the
Metabo was a little front-heavy. It was also the heaviest
overall, which made it slightly harder to aim when starting
holes on vertical surfaces.
Grip. You can hold these
rotary hammers two ways: with a pistol grip or in-line. For the
pistol grip, you hold the tool fully by the handle, pulling the
trigger with your index finger. In-line, you grip the back of
the motor housing, push in-line with the bit, and pull the
trigger with your ring and pinkie fingers. All of the models
except Metabo provide rubber surfaces and grooves for in-line
gripping, which I like. The Metabo has grooves but no rubber
The Hitachi (top) and the Makita have
different selector switches, but both are easy to
Side handles. All side
handles were satisfactory. Hilti's and Metabo's are rubber
coated and the most comfortable.
Triggering. The Hilti was by
far the most comfortable to grip, with a large,
easy-to-activate trigger accessible in both grips. The Makita
and the DeWalt felt good, too. I could reach their triggers
with two fingers in-line, even with gloves on. And, when you
pull the Makita's trigger, a handy work light comes on, which
is great for dark spaces.
I have larger than average hands, but some of the triggers were
hard even for me to reach when holding the tools for in-line
operation. Hitachi's reverse switch obstructs the trigger a
little; with gloves on, I could reach it only with my pinkie.
Bosch's trigger was pinkie-only without gloves. Metabo and
Milwaukee both have readily accessible triggers, but both
handles felt much too wide, which made holding them in-line
less comfortable. On the Milwaukee, I could really feel the
tool vibrate when I held it in-line. Metabo's trigger spring
was stiff, which made using it in-line difficult, and the
reverse switch hit my finger in the pistol-grip position.
Bit Holders, Depth Stop, and
A free-spinning collar on the bit holder's nose helps protect
the bit holder itself from impact, as when the tool thrusts
into a cavity in block. More important, it protects the end
seal. The end seal keeps abrasive dust out of the bit holder
and helps keep the grease inside from escaping. Since an
expensive bit holder is the most common replacement on these
tools other than brushes, that detail is important to me.
Metabo's metal collar is the toughest. All the bit holders
free-spin except Hilti's.
Hilti acknowledges the importance of a good end seal, however,
and is the only company to mention it in the manual, offering
it as a replacement part for less than $10.
Depth stops. The Bosch,
DeWalt, and Milwaukee depth stops have positive locking notches
that stop the drill solidly every time. And their easy lever
adjustment was quick and didn't require loosening the front
handle, as was necessary with the Hilti, Hitachi, Makita, and
Metabo. I could defeat these four friction-held stops by
pushing moderately hard or bottoming out hard a few times. If
you crank them down tight and then watch carefully as you
bottom out, they work fine.
Clutch. It's an unwritten law
that rotary hammers have a clutch, and for good reason: When
bits stop in concrete, it's sudden and it's solid. A good
clutch also provides peace of mind, because it means I don't
have to maintain a death grip on the tool to keep it from
injuring me if the bit snags on a piece of rebar.
I tested the clutches by impacting a spinning bit against rebar
inside a hole, and then doing a physical evaluation of reaction
torque (again, no test lab equipment in sight). In other words,
I felt how hard they twisted against my grip. The Makita,
Bosch, and Hitachi had low reaction forces, while the Hilti and
DeWalt had higher, yet manageable, forces. The Milwaukee's
motor slowed and strained, almost stalling before the clutch
activated with high force.
Metabo's clutch action is electronic and reduces power to the
motor when a bit jams. At first, I thought there was no clutch
action, because instead of the mechanical clutch clatter that
is audible on the other tools, the motor slowed and made
straining noises as the bit jammed. The tool put up a fight,
requiring a high reaction torque to engage the electronic
clutch. When I hit rebar on the job site, the Metabo was the
only one in the group that spun out of my grasp. It gave me a
good whack while wrapping its cord around itself and bending a
Hilti's precision hammer setting is great
for working in softer materials like brick.
The DeWalt, Hitachi, Makita, and Metabo have a useful chipping
function. I tested the demo capacity of these small tools with
bull-point and cold chisels. The Metabo, Makita, and DeWalt
were lighter-duty chippers, as expected for modestly sized
tools. But the Hitachi amazed me — its superior piston
effectiveness drilled a bull-point chisel 2 to 3 inches deep in
the test concrete in mere seconds. Count on any of these models
to pop up tiles and start holes, but expect more demo power
from the Hitachi.
All the hammers I tested came with plastic cases that met my
requirement of fitting the tool with the side-handle on. They
all easily withstood my "stand on and bounce" test, too. I
really like the long-bit storage compartments in the Bosch,
Metabo, Hitachi, and Makita cases; they keep bits from rolling
around in the box. The Hilti and DeWalt cases provide a
dedicated area only for short bits. The Milwaukee case is
limited to storing six short bits in slots. The one-piece Bosch
and Hilti latches look upside down — I suggest labeling
the top of the box to make it obvious which end is up. The
Metabo case is the only soft, blow-molded model, which seems
oversized and a little flimsier than the rest. Instead of an
articulating hinge, it has thin plastic connecting the two
halves at the bottom.
I studied each tool's manual, looking for recommended usage
techniques, technical details, maintenance and warranty
information, and an obvious toll-free number. Each manual was
fine. Out West, where I work, a Spanish-language section is
important, too, and all but Makita included it.
The Hilti and Metabo models are the most versatile in the
group. Hilti's bit holder is easily removable and can be
effortlessly replaced for maintenance without tearing down the
tool, or it can be exchanged with a high-quality keyless chuck
accessory ($95) for smooth-shank bits. It also has a unique
precision hammer feature that reduces the percussive force
output. While I had to refer to the instructions to figure out
how to use the dial that engages this feature, it was perfect
for drilling holes for Tapcon screws in soft brick on an old
house remodel. The other hammers were too aggressive and
oversized the hole in this material.
The Metabo has a lot of ambitious
features like chipping and multiple speeds. It's also the only
tool to ship with a keyless chuck accessory for wood-boring
The Metabo was the only hammer to come standard with an
accessory keyless chuck — a nice feature that makes this
tool capable of using both smooth-shank and SDS-Plus bits right
out of the box. That, combined with its speed-selection dial,
made it the right candidate for stirring a five-gallon bucket
of paint at a nice slow speed. Both Hilti and Metabo have
dual-speed ranges in drill-only mode that make them useful as
multipurpose rotary hammers and drills.
While all the tools tested have a drill-only feature, and you
can purchase an accessory chuck for smooth-shank bits, they're
not perfectly suited for heavy drilling and driving because of
the clutch action. In fact, Makita's directions say not to use
it with a hole saw because the clutch may engage too
frequently. I have a spare 1/2-inch drill, anyway — my
10-year-old hammer drill.
Makita's well-placed work light turns on when you pull the
trigger, which is good for dark spots.
On the job site, drilling and chipping performance are my top
priorities. Performance in the timed drilling trials clearly
determined the winners for me. For getting holes drilled with
power to spare, the hands-down best performer was Hitachi. It
won every single drilling trial and was great on site. Nothing
I did could slow it down when it was drilling or chipping.
Makita earned a close second, taking second in every one of the
trials. Hilti gained third with solid performances and great
comfort. Bosch's dependable power took fourth, with DeWalt
close behind. The Metabo, while the most versatile multiuse
tool, was a little slower drilling and chipping. The Milwaukee
model brought up the rear.
is a designer-builder in Boulder, Colo.
This article was reprinted by permission of Tools of the
Rpm / Bpm
0-1,350 / 0-6,000
0-1,100 / 0-4,200
Modes of Operation
This is the least expensive tool in the test and
delivered dependable power and low vibration, even when
pushed. It doesn't have a chipping function, but I do
like the dependable depth stop and the tough box, which
stores long bits. Also, the tool feels extremely light
in use. The tool body is tall, which makes holding it
in-line and reaching the trigger a little difficult.
The clutch engaged quickly when the bit jammed
The DeWalt delivered consistent drilling power all
the way through the test. I like the trigger on this
tool — it's easy to reach and squeeze either
in-line or with pistol grip. It also has a useful
chipping feature that works for popping up tiles and
light chipping. The box could be better: There is a
compartment only for short bits. It took a pretty high
resistance for the clutch to engage.
Rpm / Bpm
0-930 / 0-2,400
0-1,150 / 0-4,600
Modes of Operation
I really like this tool for its unsurpassed comfort
and versatility, plus its good power. It has the best
trigger — easy to reach and squeeze from any
position — and the precision hammer feature is
great for finicky materials. The selector dial sent me
to the instructions to figure out what the icons meant.
The box could be better, too: There's a compartment
only for short bits. Its clutch is less sensitive than
that of the other tools.
This tool is a real winner. It was the fastest and
most powerful in every drilling test. It is comfortable
to hold, chips like crazy, and has a perfect clutch
action. The only faults I could find were that the
reverse switch obstructed the trigger somewhat in the
in-line position and the depth stop could be
UHE 28 Multi
1 1/8 inches
Rpm / Bpm
0-1,100 / 0-4,500
0-950 / 0-4,400
Modes of Operation
two drilling speeds
This tool is a powerhouse. It scored high marks in
every drilling test, with plenty of power and speed. I
really like how easy it is to reach the trigger and
that I can chip effectively with the tool. Its clutch
kicks in a little too easily for my work. It's got a
handy work light.
This is a sophisticated tool. If I could have only
one drill for wood, concrete, and everything else, I'd
pick this one. It ships with a keyless chuck accessory
for smooth-shank bits. Two speeds in drill-only mode
meant I could use it like a standard drill. It chips,
which is very handy. It doesn't have the most concrete
drilling/chipping power, and the clutch takes high
reaction torque to kick in. Its wide tool body makes it
somewhat uncomfortable to hold in-line.
Rpm / Bpm
0-1,270 / 0-5,400
Modes of Operation
While the Milwaukee has a nice trigger design, tool
body, and depth stop, the tool didn't deliver the power
I need. It really labored when taxed, and the clutch
took a long time to kick in. It doesn't chip, and the
box has compartments for only a few bits. Its five-year
warranty is the best in the group.
Electric Tool Corp.