No, we (the UK) are too small of a market.
There is an NZ company called Belmont whose founder is/was a target shooter. They got established at the right time (1967) when commercial venison hunting took off. At one point, NZ hunters used more ammo than the NZ Defence Force!
Their proximity to Australia and ADI (who make a lot of powder) helped too. Heck, Australia used to have quite a few factories, ICI, Winchester-Olin etc.
As far as I'm aware, only
@Edinburgh Rifles and HPS are actually assembling centrefire ammo in the UK for the civilian market. All of this relies on imported components at the moment, so I'm not sure where a saving can be made.
There are also some jokers passing off their unproofed reloads as saleable ammunition, just because they have an RFD license.
What would really stir the market would be something drastic like opening all public land in Scotland to deerstalkers, but I doubt that would ever happen as politicians like nothing more than control and restrictions, as recent events have demonstrated.