Some velocity may help at 200 yards, but you probably won't increase your muzzle velocity more than 100 fps. The improvement to your trajectory and fpe wouldn't be that noticable. 200-500 fps in a firearm is notifcable. Sounds like your Mrod is very shooting very good. Chrono to see how fast you a push your pellet to stay accurate and still be sub sonic. Then download a ballistic chart with your settings. Long range shooting is very dependant on consistant accuracy, range compensation (bullet drop), and wind allowance (drift). Please let us know your results. Good luck