Want to build a general purpose rifle for all North American game. Looking hard at the .338 Sin in a 20-22" barrel with a brake. Will be using 225 gr. Barnes bullets @ 2,800 fps and wanting a repeater with at least a two round magazine capacity. I know I can meet my guide lines with the .338 Norma Magnum but it appears simpler to build the .338 Sin. I have read all of the post I can find but am still confused. I have found references to using both RUM and 330 Dakota brass for the parent case. With the RUM brass the case must be shortened and then hydro-formed. It appears that the Dakota case was run through a Sin sizing die and then fire formed. Which method is correct and is any prepared brass available for the Sin? I do not want to do the simpler build to only have an on going pain in my butt forming brass.