20/10/2016 8:41 AM AEDT | Updated 20/10/2016 10:21 AM AEDT

Leyonhjelm Concedes Abbott May Not Have Known About Gun Deal

But the Senator insists the deal did happen.

Andrew Meares, Fairfax

CANBERRA – Crucial Senate crossbencher David Leyonhjelm has accused former Prime Minister Tony Abbott of "mischief" and questioned the trustworthiness of the Turnbull Government as he continues his claims he has been "dudded" on a potential guns for votes deal.

But Leyonhjelm has conceded it is conceivable Abbott, as Prime Minister, did not know about the deal to secure Senate votes for a relaxation of the ban on the controversial seven shot, rapid fire, lever-action Adler A110.

Leyonhjelm insists, "I am not suggesting (Abbott) knew personally, but there is no chance the Prime Minister Minister's office did not know about it.

"It did happen. Not only was there a deal, the deal got acted on.

"I have been done over badly."

Confusion remains over whether the both Abbott and Turnbull Governments have negotiated with the Liberal Democrat Senator to secure his Senate vote on migration and industrial relation legislation in exchange for a lift on the gun ban.

Prime Minister Malcolm Turnbull insists the national gun laws are "set in stone," while Tony Abbott, on ABC 730, flatly denied he did a gun deal with Leyonhjelm as Prime Minister.

What it is about the Adler shotgun?

A temporary ban was placed on the seven-shot, lever-action shotgun in 2015

A magazine can be emptied in a matter of seconds

It can fire seven rounds with capacity for an eighth

Proponents want it help deal with feral animals

Opponents say it is too powerful and could end up in the wrong hands

Leyonhjelm has produced an email exchange which he said proved a deal was struck with Abbott government ministers Michael Keenan and Peter Dutton, but that was dismissed by Abbott on ABC 730 as an email from a staffer.

"No deals from me," the former Prime Minister declared. "No deals from my office. No deal."

Leyonhjelm insists he asked the Immigration Minister Peter Dutton for the relaxation of the gun ban when he came to ask his and Senator Bob Day's support for a migration bill.

"We said that is the price. Nothing personal, Peter. You want our vote. We want this," Leyonhjelm told reporters in Canberra.

"He agreed."

Leyonhjelm has declared he would have trouble doing a deal with the Justice Minister again, questioning his trustworthiness.

Abbott also rejected suggestions that he is undermining his successor by speaking out on Australia's gun laws.

The former Prime Minister tweeted concerns about "horse trading" on gun laws on Tuesday but told ABC 730 Wednesday he was "chiding" Senator Leyonhjelm, not Turnbull.

"The question is, why is he saying anything at all? You would have to assume he has mischievous intentions," Leyonhjelm said.

Leyonhjelm has also complained he, and other sporting shooters, are being vilified over support for guns.