Re: A few questions from a newbie
Longer barrels might provide 30-70 fps per inch. You might get some good return with a longer barrel on the ulramag.
The minutes of angle adjustments change in your turrets as the distance changes. Simply think of one minute equals one inch at 100 yards, two inches at 200, three inches at 300 etc.
Your drop of 6" at 300 is the same as two minutes since each minute is worth three inches at 300. You need two minutes up, if your turrets are marked as 1/4 minute per click, you will need eight clicks.
Most turrets can be zeroed after you have shot the rifle and got the point of aim and point of impact where you want them. There may be little setscrews on the turret which when loosened enable the turret housing to free-wheel so you can line the "0" up with the index mark. Some turrets have the housing fitting on splines so you just loosen a top screw, lift the housing straight up, line up the "0" with the index mark, drop the turret into the splines and tighten the top screw.
Working from "0" you do not have to count clicks - you just go to the number 2 and you have two minutes up.
Good luck with this, after a while it is very simple. Just have to do it a bunch.