Lucas/Members while giving advice to Lucas , please elaborate on the shot gun action ga that is suitable for a conversion build..I spoke to a friend of mine..Johan Greyling..he mentioned that most people use a 12 ga action ..according to him this will makes for a heavy , slow target acquisition , slow handling heavy type of rifle...I am considering a .450 NE nr 2 Jeffery as my second build ..my first conversion build I am contemplating a 16 ga shot gun action building a 45-70 Government double rifle ...any comments and suggestion will be much appreciated as pointed out by Lucas as well..I need to point out as well that I want to keep the original shot gun barrels and build new 45-70 cal Government rifle barrels ...