Over 17,700 weapons were handed in during the first week of the national knives amnesty, the Home Office said.
Carrying a knife can land you a four-year jail term
Machetes, meat cleavers and axes as well as knives were among the haul of 17,715 surrendered to the 43 police forces across England and Wales.
Home office minister Vernon Coaker said the results were "encouraging".
The five-week amnesty, running until 30 June, allows people to surrender knives at police stations without fear of punishment.
Mr Coaker urged those who had not yet handed in their weapons to do so.
"The initial figures for the first week of that campaign are very encouraging, " he said.
"That is 17,715 fewer weapons that can be used in a crime against ordinary, law-abiding citizens.
"If you carry a knife out of self-defence, you run the risk of having it turned on you. Carrying a knife is illegal and will not be tolerated. It could land you four years in prison"
As well as knives, Devon and Cornwall police also received an 8lb anti-tank rocket launcher, known as a "tankbuster", which has a range of up to 350 metres.
A force spokesman said: "The amnesty is for all weapons and if someone wants to get rid of a rocket launcher, that's fine by us."
Devon and Cornwall's assistant chief constable, Tony Melville, who is also a member of the Association of Chief Police Officers, said the haul was "a significant step towards making our streets safer".
The initiative, running in England, Wales and Scotland comes amid growing concern at the level of knife crime in the wake of a series of fatal stabbings.
Police say that from 1 July tough action will be taken on those found armed with knives.
However, some families of victims of knife crime have questioned the effectiveness of an amnesty, calling instead for tougher sentencing.
Last month 15-year-old Kiyan Prince died from a stab wound after being attacked outside his school in Edgware, north London.
And last week Alex Mulumba Kamondo, also 15, died after being knifed through the heart during a street fight in Lambeth, south London.