Quote Originally Posted by Peter Dunkley View Post
OK folks, just found out how it can be done. Thanks for looking.
Hi Peter, only just caught this. Try looking at Rocky Mountain Cartridge brass, Okay it has to be imported from the US but a quick e-mail should establish if the 12g brass is equipped for shotgun primers (their .410 brass is), price list here:

https://www.rockymountaincartridge.c...oad%20Kits.pdf

Worth a look if avoiding re machining faff is an issue.