Ok…… 509-600 yards. I wasn’t too concerned with the definition of long range. Whatever any of you consider long range, be it 300-400-500 whatever. What do you like to shoot? I have plenty of prone type comfortable shooting opportunities here in Saskatchewan on whitetail at all kinds of ranges. I just want another rifle to complement my 30-06 cause buying rifles is fun.
Your 06 is plenty capable. I killed a deer at around 550 yds with a 168gr Ballistic Tip from an 06.
The next logical step up from your 06 would be a 30 cal magnum, of which there are numerous different flavours. By "magnum" I mean a WM, WSM, PRC etc. The magnums should take you out to 1000 yds no problem.
If you want to go further, you will need to be looking at one of the larger format rounds like the 300 Norma Mag, 338LM etc.
A lot of the people putting limits on range and saying it shouldn't be done, likely haven't done it or even shot at any sort of distance. For the vast majority of shooters, 300 yds is long range.
From personal experience I can tell you that you will need to practice at distances way past the distance you plan to hunt at. For example, I did a lot of shooting at 800-1000 yds, so when it came to making a 500+ yd shot, that was a lot easier than what I had practiced at. Long range shooting and hunting requires a lot of practice regardless of what you are shooting at. Understanding the wind is a thing.
With respect to optics, I would say that anything in the 16x-24x range is sufficient and the 24x is the practical limit for magnification in the field. You will need a ballistic computer and some experience with how it maps your chosen round at distance. You will need a decent spotting scope. I use a spotting scope with a MIL reticle so the spotter can speak the same language as my rifle reticle and turrets. This will make corrections a lot easier.
Long range shooting is a team sport and long range hunting really demands a competent spotter. You will need to find a partner who is also a competent shot to help with spotting. Military sniper teams often put the best marksman behind the spotting scope and it is the spotter who calls the corrections.
You will need some means of accurately determining the range to the target. Range estimation is critical.