So I'm thinking about building my first rifle. Here's what i know:
1- i want a single shot
2- i will most likely start with a model 12 223 single shot
3- will probably want a 220 swift or 22-250 (possibly AI)

what I don't know:
1-are those even possible calibers (starting from a single shot 223)
2- what parts and tools i need to do so

also opinions from those in the know

i did try several searches but didnt really find the kind of help "I" need lol