Dean Broadway (40) of Mablethorpe Road, Paulsgrove, was jailed for five years on Friday (May 13) after pleading guilty to possession of a section five firearm.
He was also sentenced to two years for possession of section one ammunition, to run consecutively.
The charges followed a search of his address on April 13, 2016.
He was also sentenced to two years for possession with intent to supply a controlled drug of Class A (cocaine) from September 2015, also to run consecutively.
PC John Middleton said: “Mr Broadway received a lengthy prison sentence for possessing a dangerous weapon. The level of threat, risk and harm to the community could have been significant had we not located this firearm and the ammunition with it.
“Police take any offence in relation to firearms seriously and I would recommend any member of the public to report any firearms related incidents to the police.”
If you have any information call 101, in an emergency call 999, alternatively you can call Crimestoppers, anonymously, on 0800 555111.