A fifth person has been jailed for her role in a family-run illegal gun operation.
Trudy Bates, 26, of Birmingham, was found guilty of conspiring to sell ammunition and was sentenced to two years imprisonment on Friday.
Arms found by police have been linked to over 20 crimes, including the murder of Carl Campbell in 2016.
Kevin and Connor Bates were arrested after their home on North Roundhay in Kitts Green was raided and five illegal firearms as well as ammunition were recovered.
Makeshift workshops were discovered in the garage and utility room which were being used to shorten shotgun barrels and modify ammunition.
West Midlands Police said between December 2014 and July 2016 large purchases were made by Bates, of Peplow Road, which are believed to have been for equipment to make ammunition for obsolete calibre firearms, vintage weapons for which ammunition is not readily available.
These would then be supplied to criminal networks, according to the force.
Det Supt Damian Barratt, from the regional organised crime unit, said: "The investigation revealed it was a truly family affair."