More than 340 weapons were surrendered as part of the two week scheme of which 220 were ‘live’.
About one quarter of the weapons will be forensically tested for links to reported crimes.
About 11,000 rounds of ammunition were also handed over to police during the amnesty which ended yesterday.
Scotland Yard launched the initiative to give members of the public the chance to dispose of weapons anonymously.
A similar scheme was run six years ago which only collected 62 weapons.
Detective Chief Superintendent Dean Haydon, of the Trident Gang Command, in the Met police says it is unlikely that hardened criminals and gang members will hand in their firearms.
But it could allow people who own an antique or ‘curiosity item’ which realise is too dangerous to be kept.