Hello everybody. I was reading my new issue of rifleshooter yesterday and I came upon an article about cartridge efficiency. They kept on talking about a cartridge that I had never heard of before, a 5mm-35 SMc . They claim that these SMc cartridges are the ultimate in efficientcy and that it shoots a 40 grain bullet at 4700 fps without any more barrel wear that a 223 rem simply because of the very short, fat case and a somewhat rounded shoulder. Has anyone else heard of this cartridge? I would like to know more. What does SMc stand for and I it accurate? The article says that savage is chambering some rifles in this caliber through its custom shop. Any info is good. THanks