i plan on building a 6br for mostly varminting and target shooting,,not competion just to pass time between varminting) and realize a smaller bullet would be fine. i want to know what about upping size in bullets: i can obviously see that a 6br loaded with a 105 grain bullet will not fit into the same chamber as a 6br loaded with a 75-80 grain bullet, or will it? im just looking for the most extreme range i could shoot between bullet size, and not have to wonder about the bullet and casing not fitting into the chamber or the bullet itself going too far into the case. thanks again, still a complete newb at all of this!! open to all kinds of suggestions!