There is no ammo 5.6x50R available but I have been able to get brass, RWS and S&B off the internet, single shot break actions don't go through a lot of brass. Dies were off the shelf from Hornady and C&H carries them also. Hornady has load data.
I had a combo gun in 222 Rem/12ga and seriously looked into 222 Rimmed but the only factory brass was Bertram and I've had poor luck with their stuff in my 6.5x58R Sauer. Brass can be made from 357 Max but it is a lot of work.
