I shoot a 270gr Speer GD with 130gr 777 pellets in a TC Black Diamond XR and formerly in a TC Encore (both 26" barrels). I zero at 100yds and have 12-14" drop at 200 (I try to sight in with temperatures close to what I typically hunt in - approx 40 degrees). I personally would not hesitate at 200yds if the conditions are right. So I'm guessing a 300gr with 120-130gr pellets would be more than sufficient. I'm not a big fan of 150gr charges, but that's my preference. If accurate and consistent enough, 150gr pellets and a 300gr Barnes would do what you want. BUT you really need to shoot whatever load you decide at all ranges (50, 100, 150, 200) and in different weather conditions (cold, warm, rain, etc...). Particularly cold and warm. Zero'd in with 70 degree weather typically will not be zero'd in with 15 degree weather.