When I started the post, I figured Retro and Obsolete are two different things. I still think this.
Retro is an oldie-but-goodie that may be past its prime but is still holding on.
Obsolete is: no one really chambers this cartridge anymore because something else has come along that is easier to deal with and performs just as well if-not-better. Kinda like the 7x57 Mauser or 7mm STW or 300 H&H.
