Nigel Farage has called for an easing of the ban on handguns imposed after the Dunblane massacre.
The Ukip leader branded the current law "ludicrous" and insisted it had not helped to keep gun grime down.
He also dismissed his party's 2010 general election manifesto as "drivel", saying it had been written by an "idiot".
The comments came in a tetchy appearance on LBC radio after difficult week, which has seen a Ukip councillor link gay marriage to flooding and Mr Farage argue that women are worth less to City firms than men.
Ownership of most handguns was made illegal by John Major's government following the 1996 Dunblane shooting, when Thomas Hamilton killed 16 schoolchildren and a teacher before shooting himself.
Tony Blair's Labour government then extended the restrictions in 1997 to cover all handguns, including the .22 pistols used at the Olympics.
Asked whether he thought the controls were right, Mr Farage said: "I think proper gun licencing is something we've done in this country responsibly and well for a long time, and I think the knee-jerk legislation that Blair brought in that meant that the British Olympic pistol team have to go to France to even practice, was just crackers.
"If you criminalise handguns then only the criminals carry the guns.
"It's really interesting that since Blair brought that piece of law in, gun crime doubled in the next five years in this country."
He added: "I think that we need a proper gun licencing system, which to a large extent I think we already have, and I think the ban on handguns is ludicrous."
Mr Farage also sought to explain a floundering appearance in a BBC interview yesterday, when he seemed unaware of previous party policies such as repainting trains in traditional colours and setting uniforms for taxi drivers.
The MEP - who had briefly stood down as leader at the time to focus on an unsuccessful run for a Commons seat - told LBC he had not even read the document.
"I didn't read it, it was drivel, 486 pages of drivel, I didn't read it, nor did the Party leader, it was a nonsense, and we've put that behind us and moved onto a professional footing," he said.
"We had a manifesto, and I'm going to put some inverted commas around it that was produced in 2010, it was basically a series of policy discussion papers that was put up on the website as a manifesto.
"It was 486 pages long, I'm pleased to say that the idiot that wrote it has now left us and joined the Conservatives, so there is some traffic going back the other way, and they're very welcome to him."
David Campbell Bannerman MEP was the main author of the manifesto, and is now a Tory.
Ian Mearns, Labour MP for Gateshead, said: "Families facing a cost-of-living crisis will find it bizarre that one of Nigel Farage's priorities would be to relax Britain's tough gun controls.
"This, from a man who thinks prostitution and hard drugs should be legalised, is further proof of how dangerously extreme Ukip are."