A new offence of getting someone to mind a gun or other weapon will come into effect in England and Wales from 6 April, the Home Secretary has said.
The summits were held after a spate of gun crimes in London
The previously-announced measure is being brought in early as a response to a spate of gun crimes in London.
John Reid was speaking at a second summit on gun crime with community leaders and police.
The Society of Black Lawyers accused ministers of a "knee-jerk" reaction which ignored gun crime's root causes.
Mr Reid said: "These roundtable events provide a real opportunity for people living in communities affected by gun crime to influence our work in this vital area."
He also said an order to extend the minimum five-year mandatory sentence for possession of an illegal firearm to those aged 18-21 would be laid before parliament shortly.
The new offence of minding aims to target gang members who seek to avoid prosecution by getting others to hold their weapons.
Funding to help community groups tackle gang-related crime was outlined at the first summit hosted by Tony Blair at Downing Street.
The Society of Black Lawyers said tougher sentences would not address the root causes and described the summits as a "photo opportunity".
It said the demand for Class A drugs was the fundamental cause of gun crime among teenage gangs.
Chairman Peter Herbert said: "The time has come to invest in young people, to remove the poverty which is the breeding ground for serious gun and drugs crime, to begin pilot studies to treat the addicts which feed the drugs market in Britain and make it totally uneconomic for hard drugs to be traded on our streets".
He said the sale and ownership of all replica weapons needed to be banned and called for "real alternatives" to imprisonment.