first of all--judging distance while trying to humanely kill large game is a NO-NO--i dont care how good you think you can judge distance you arent good enough to consistantly come within 10yds all the way out to 1000--NO WAY IN HE!!
best bet would be to get whichever leica rangefinder you can afford (300-450$) -- your quarry deserves to be ranged accurately if you are gonna wing shots past 1/2 a mile at them.
aint nuttin out there flat enough to make up for bad judgement!!
for whitetail and below the 6.5-284 would probably be enough for 1k or a little more--for anything bigger, the 7mag or 7wsm would be a good choiuce with recoil in mind--make sure you muzzle brake
it at 10-11 lbs!