OP, if your looking to stretch it out, which is going to be hard unless you've changed elevation turrets on your VX-II. The best bet is with the Spitzer boat tail bullets like the Accubond, Interbond, TTSX, Scirocco, etc. The flat base bullets like the Partition, A-Frame are great bullets for sure, however, the flat base does not lend itself as well to long range shooting. Will they work? Of course, with more drift, more drop & less pop at range than the same weight boat tail.
Now, i'm guessing (i know, i know), that you are looking for factory loads, so your selection is going to be reduced compared to those of us who handload unless you order from a custom loading company such as Superior etc.
If you pick the TTSX, TSX, MRX, Scirocco etc. DO NOT mix these bullets with conventional jacketed bullets; the material in these bullets are different & will foul your bore badly as the two different materials layer up (ask me how I know that
). Start with a VERY clean bore before shooting these & you will be MUCH happier...
Take the time to play around at the ranges you're talking about & get to know how much drop you are going to have when moving from your zero to 400+. If you're really serious about long range, it may be worth upgrading your optics.