Following my advice....that's not going to end wellMany thanks for the responses on this. At the suggestion of @Daz I went and got a Titan SDS drill which went through the lintel very easily using only 40% of it's power.
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Quite a bargain from Screwfix; 1500w hammer drill, 3m cable, conventional drill chuck and a number of sds drills/chisels, all for £60!
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