I recently acquired an accufit stock that was a 10 tactical in 308 top bolt release. the barrel and magazine were not included......so I am going to build a 6x45 and what I need to know is what bottom metal do I need to make it accept a 4 round magazine......I have the trigger guard and the floor plate that held a larger capacity 308 and I am not sure if that will work with a 4 round 223 mag.......I do not know if there is a larger capacity mag for 223 so that is my delima.....thanks