This test used a 32m speed bore bit through a marocarppa sleeper

The tools used are the Makita BHP454 with 3amp hour Li-ion batteries (claimed), Hitachi DV18DL with 3 amp hour Li-ion batteries (claimed). Milwaukee 2611-20 with 47 watt hour Li-ion batteries (claimed ). And Dewalt DCD970 with 36 watt hour Li-ion batteries ( claimed ).

What's the difference between amp hours and watt hours? Some of the manufactures use watt hours and some amp hours they tell us the same thing, how much storage capacity the battery has. There is a simple equation between them. Watt hour divided by the voltage of the battery equals the amp hour.

Therefore the Milwaukee at 47 watt hour is 2.6 amp hour and the Dewalt is 2 amp hour.

We would like to clear up some confusion on Milwaukee products, the 2611-20 is the US part number for the product which we import. It is also known as the HP18PD-32C which is the European part number for the same product imported by another tool importer.

Milwaukee USA don't put an amp hour on their batteries where as Milwaukee Europe claim theirs to be 3 amp hour but also have 47 watt hours printed on them which by the laws of physics can't be true. We believe the US and European batteries are the same 2.6 amp hour.

We had to speed up the footage to stop everybody falling asleep.

The Makita came out on top with what we believe to be the only genuine 3 amp hour batteries with 20 holes the Milwaukee 2nd with 18. Both these drills had plenty of power to perform the test. The Dewalt only achieved 11 holes which was very disappointing but fits with it the having the smallest capacity batteries at 36wh (2ah). The drill also had plenty of power to perform the test. The biggest surprise was the Hitachi which couldn't drill all the way through without cutting out. We tried this test several more times with the Hitachi to try and get a score and the most it achieved was 15 holes with lots of cutting out.

We think the Makita is the best product here for outright power and endurance with light weight and good balance. The Milwaukee comes second in the test but has proved to be the least reliable brand of the 4 out in the field. The Dewalt has suffered badly with change over to li-ion battery technology, it has fallen a long way behind Makita with the run time of its batteries but the drill is well built and reliable and is the only one with a 3 speed gearbox.

The Hitachi struggled in this test because of a lack of power but has proved to be a very reliable drill in the field.

Score out of 5

Makita 4 best all round performance and reliability.
Milwaukee 2 Good power but let down by poor build quality.
Dewalt 2 Good drill let down by rubbish batteries
Hitachi 2  a very reliable tool let down by a lack of grunt