This is a really debateable question. My advice is determine what your max range will be. For example I don't like to shoot at an elk futher than 400 yds. Then with the help of your local gun dealer pick the lightest, softest-recoil rifle that will cleanly kill an elk at that range. Remember the more you like to shoot your rifle the more accurate you'll become and if it kicks like a mule, more than likely it will collect a lot of dust. But on the other hand you certainly wouldn't want to attempt a 400yd shot at a big bull with a 30/30. I use a 7mm Rem Mag with 175 and 150 gr partitions. I also like the 30 caliber mags but they are a little heavier. There are lots of guns that will kill an elk but the range is a little different with each one. Stay with the "tougher" bullets like failsafes, barnes X, bear claw or partitions. What grain to use will depend on the rifle.