I am also a full time pest controller & I have a .410 shot pistol, which I use for despatching trapped pests & vermin etc, but it also states on my FAC I can shoot vermin in & around buildings, which I was doing on the weekend, shooting rats up a tree which had taken refuge from the dogs while we were smoking them out. I have an open FAC, plus I have SGC with a few .410 shotguns on it, one with a moderator on. These .410 shot pistol are not much use beyond five metres, as the spread of the shot is too great for any accuratecy. If you have a FAC & you have a good reason to own a .410 shot pistol, they cannot refuse you, it is your right. When I first applied for mine a few years ago, the FLO tried to persuede me to have a .22rf pistol instead, saying the Police armourer reccommend that I had it. But I refused & stuck to my guns (no pun intended) saying it is safer to use a .410 shot pistol than a .22rf pistol & how many trapped foxes do the armourer shoot, the FLO said fair comment. Within two weeks I had the go ahead to purchase a .410 shot pistol.