OK, so maybe I missed it but what rangefinder do you have? Once you pass 300 yards you need to do better than guessing at the range. Are you going to get yourself a wind meter ? With a good rangefinder and some practice, you can get the elevation down pat, then it is the wind deflection that is going to get you.
Speaking of which, what bullets are you shooting ? For long range you need to shoot bullets at the top end of the weight spectrum that have the highest BC your barrel can manage. The good thing is that 270 has some good bullets available. The bad thing is that perhaps your barrel may not be able to stabilize them. Berger makes a 150gr Hunting VLD with a G1 BC of 0.531 which is pretty good. It needs a 1:10 twist barrel to shoot it though. What is your twist rate ? A look at the Hodgdon reloading site shows 150gr bullets going 2850 fps at max loads (from a 24" barrel). Plugging that into a ballistic program yields the following:
Range Drop Windage (10mph left) Velocity fps Energy ftlb
0 0 0 2850 2705
100 0 0.6L 2673 2379
200 -1.5 1.2L 2502 2085
300 -3.7 1.9L 2338 1820
400 -6.4 2.6L 2180 1582
500 -9.4 3.3L 2028 1369
600 -12.7 4.1L 1882 1180
700 -16.5 5.0L 1744 1013
800 -20.6 5.9L 1613 867
900 -25.3 6.9L 1492 741
1000 -30.5 7.9L 1380 684
So a few things to note: At 1000 yards (with a left crosswind of 10MPH) you end up with 684ftlb of retained energy at a velocity of 1380fps. The energy is equivalent to the muzzle energy from a 10mm handgun or from a 55gr 223 bullet at 300 yards.
Most scopes with 1/4MOA clicks will dial 12MOA per turn on the turret. So you can see that gets you just short of 600 yards on a single rotation. To go past 900 yards takes more than 2 turns, just less than 3 turns to get to 1000 yards. That windage doesn't look so bad until you realize that a 10mph wind speed miss-call translates to 83" of displacement at 1000 yards. For that reason, one needs a wind speed meter in the field. Even then it still takes judgement to know how the wind flows over the landscape.
So my recommendation is as follows:
1)Find out your barrel twist so you know if it will stabilize heavy VLD type bullets.
2)You will want to do your own reloading, since VLD hunting ammo is very expensive to buy and it gives you control of all the variables that influence accuracy from the ammo point of view
3)You are going to need good glass in the way of binoculars, rangefinder and scope. I suggest you consider the Vortex PST 4-16 or 6-24 scopes. The 4-16 saves you a bit of money, for all practical purposes 6x is a pretty good Min hunting magnification that you are familiar with. If you get the second focal plane scope, they run about $750 at opticsplanet and you will not regret the decision. You have to spend substantially more before you might see any improvement in quality. Get at least a 1000 yard rangefinder from Nikon, Leupold, Vortex, Leica or Swarowski. If it says 1000 yards, they probably mean 800 unless conditions are ideal...
4)If you have not done it already, you will want to make sure the barrel is free floated and the action bedded
5) Unless your trigger is absolutely flawless, you will want the trigger tuned. The trigger alone can have a pretty big impact past 300 yards. Usually safety dictates not much less than 1.5lb on a field gun, but it needs to be crisp and creep free.
6) You will need a good rest. At least a bipod on the front and a bag for the rear of the stock. It goes without saying a decent shooters mat.
7) if you don't like your odds of shooting the breeze and missing by 80" then you need a wind meter like a Kestrel.
http://www.kestrelmeters.com/products/kestrel-4000-weather-meter
Finally a lot of practice and a way to take your ballistic info into the field with you. I have a simple table based on drop and wind drift for a 10mph wind but I would have to do some rapid interpolation if it is not 10mph. I also have the FFP version of the Vortex scope so I can directly use the reticle for drop and wind if I don't have time to touch the turret (which is the usual situation with coyotes). bearing in mind my range is limited to 450 yards currently, but then a coyote is a small target.