- take a sledgehammer to break a walnut
- take a sledgehammer to crack/break a walnut/nut
стрелять из пушек по воробьям
Three men spent all day yesterday mending my telephone. One man could have done the job in half an hour. It was like taking a sledgehammer to crack a walnut.
Англо-русский словарь идиом и фразовых глаголов. 2013.