ORIGINAL: spaniel
The only thing I'll add to Chap and lemoyne is to consider an Omega as well. They covered the best bullet choices, the Precision Dead Centers are good too but IMHO harder to get a good load developed in many guns.
I'm not the biggest fan of the Nikon Omega BDC scope due to the particular reticle design, anything with a mil-dot reticle will give you multiple better aiming points -- you'll still need to do your homework on the range to know which dot is which range with your load though.
If you really want to get accurate, get a tactical style scope so you can dial in exactly for the deer's range. My Omega wears a cheap Barska Tactical currently -- a bit of a gamble but it's working for me the last 2 years.
One thing you have to do, if you don't have one, is factor in the cost of a good rangefinder. A bushnell 400 will range reliably to 300 yards. This is an ABSOLUTE MUST for long range shooting.
I have an Omega with a Bushnell 3x5x50mm scope and it is very accurate. The only reason I didn't recommend that is I get blow back thru the breech area and it actually broke or weaken the trigger spring. I had to send it back to TC for Warranty repair, this was after 5 years of use. I looked in the manual and there were no instructions on cleaning the trigger assembly. I think the TC Triumph has corrected that problem from what I have read that Lee has posted, and he use to be a gunsmith. Anyway the Omega is a good gut but I think the Triumph is better, they are the same in accuracy in my opinion from what I have read and the price is about the same, so why buy an Omega if the Triumph is better. Chap