Thanks for the input on bullet selection on my last question. Well since i load my varmint slayers at or into the lands on my single shot guns the big question for me is having a tactical rifle built with a magazine for the first time can or should i find out ( example Seekins bottom metal is what i will be using ) what max length is for magazine, think of what bullet i want to use and deduct ? length and have gun smith ( GA ) chamber with no free bore that way i can chase throat erosion and tinker with bullet length. Well what do you think, i need some answers shooters.