WOW! these guys cover every aspect. I too would suggest some 30 grain pellets and try 120 grains with your combination. That is if you really think there is the need for you to push that projectile harder. Actually the 100 grains is more then enough for deer. As for the ability to shoot 200 yards, well there are a lot of shooters out here (me included)that can not, have serious consistancy problems or should not shoot that far simply because they are not comfortable with that kind of distance for a number or reasons. Remember, muzzleloader shooters used to be tickled to be able to shoot out to 100 yards and hit their targets..
Try the different pellet combinations listed, be sure and swab good between shots. Then, when you have time and money try some different projectiles out of the rifle like the 285 grain Barnes Spitfires. You might also want to try loose powder. Loose powder can produce some outstanding accuracy. This might increase your long range accuracy. So far I am shooting Barnes out of my Knight Disc and Wolverine only because Barnes produce the best accuracy. I hate barnes because of their cost, so I target plink with a number of different bullets, but when it comes to knocking something down, the Barnes isa great projectile.