Re: 338 lapua setup
As stated above, a 20 MOA base is usually a good idea.
So that when you get to 1000 yds, you'll be near the middle of your adjustment range and still have plenty of adjustment available for windage.
The yardage you use for your zero doesn't matter technically speaking. 173 yds, 256 yds or whatever. Ballistics software doesn't care and you can print your drop chart accordingly.
However, hunting and competition can lead to distractions. So, it helps to have something simple to fall back on and confirm.
Most shooting ranges have a 100yd line. If you ever forget whether you're back at zero or a revolution above or below it's easy to confirm at 100 yds.
I have even printed charts before using the notation 4+5.5 to indicate 4 full revolutions plus another 5.5 minutes. That's a lot easier than trying to count up 29.5 minutes on a scope with 1/10 minute clicks and 6 minutes per revolution.
My point is simply that you should develop a simple system that works for you and stick with it.