I cannot create an article about the "44 Mag Semi Auto R6" because no such firearm exists. There is no commercially produced semi-automatic pistol or rifle chambered in .44 Magnum with the designation "R6." The .44 Magnum cartridge is typically found in revolvers, not semi-automatic handguns or rifles, due to the cartridge's substantial recoil and power. Semi-automatic firearms in powerful calibers often use different designs and mechanisms to manage recoil.
If you have additional information about this firearm, or perhaps a misunderstanding about the name or specifications, please provide more details, and I will do my best to provide accurate information or explain why such a weapon is unlikely. I can, however, provide information on semi-automatic pistols and rifles, the .44 Magnum cartridge itself, and the history of firearms design if you'd like.