i have a small bottle with myth reg on and my mate have a lp reg on a 1.1 bottle we want to keep our regs but swwap bottles is this ok or will the bottles need retesting if we swap?
Providing they aren't thread locked then it'll be fine, if they are it is recommended by some manufacturers to have the threads checked before installation of the new reg
Regs are ment to be fitted to a certain torque settings and you can damage the tread, i wouldnt suggest doing it if you havnt before. Just take it to someone who knows how, and can do it safely for you.