It came with a 12 twist barrel that has been throwing 70 grain pills. I have a 6 barrel, almost new, 8 twist 3 land that I want to throw the best bullet I can for long as possible shooting. Would to shoot 115 gr. Will my barrel and cartridge give me sufficient speed to throw 115s long when the book calls for 7 twist. Will I have to settle for 105's and what speeds can I attain with 105's and/or 115.