If you are not going to hunt and only target shoot, then you will want to order your RA with a Heavy Barrel. HB option.
For 500 meters target shooting, you will likely want an XCR-M .308 or 6.5 Creedmore.
BTW Wolverine has a
used XCR-M in 6.5 Creedmore up for sale.
However, here is the rub, I have an XCR-L in 5.56, and it shoots well for a military rifle. However, no one that I know of is building DMR or match grade barrels for the XCR Platform.
Would you could do is pick up a Stag Arms Non-Restricted upper and lower and have I
nternational Barrels Inc. in BC install a match grade barrel in either .308 or 6.5 Creedmore. Add a Geissele trigger, a good Bolt Carrier Group, in Canada or from Brownells, and build yourself a darn good NR AR Rifle for less than the cost of an XCR-M.
BTW I was lucky are getting a very good shooting Black Creek Labs 102, in .308. It took 100 or so rounds to break-in, however, now with a Geissele Trigger (SSA-E), and a high-end Bushnell Scope, the 102 shoots very well out to 250 yards, which is the limit at the nearest range. I may install an IBI down the road if I find the need
beyond 250 yards.