Hoppes #9 is very poor for removing copper fouling, it's OK for removing powder fouling but limited in removing copper fouling.
KG-12 copper solvent is the best bar none, Sweets 7.62 is very good, of the Hoppes group, Hoppes BR copper solvent does work to a certain point but that's it, grab some good stuff and save your barrel the guaranteed brush wear, don't use stainless brushes and push right though in one direction only remove and repeat, dont drag it back over the crown or go back and forth inside the barrel, and use a bore guide or muzzle protector.
Asking yourself how long you want to push large amounts of patches through any barrel can be a worry, most wear coming from doubtfull cleaning practices even if done the good bear way.
It would be a fair guess that most all guns are test fired to a certain degree while held in a non moveable jig at the maker, allthough ten rounds might pull it up, the problem comes with having a new rough barrel and the copper it tears off each fired projectile, they are not going to fire one clean, fire one clean, etc etc so your just cleaning up their mess, and you should run in your barrel properly.
It's worth noting that the retailer may have used "your gun" as a new demo in the shop to show other customers which is hardly going to hurt it, but without cleaning properly by anyone who has fired it will be adding to any copper fouling you might end up with, first thing I ever do with a new gun is to smell the thing, most educated noses can tell pretty easy if it's really new, after all the test firing at the factory is done without the stock and the entire gun is then likely dunked in some kind of solvent/cleaner.
My Anschutz BR rifle was testfired as the 10 shot group shows but not with the new bolt I got with it, 100% sure of that as the receiver puts the faintest of scratches on the bolt even covered in the best oil.
Pack a lunch, fire one and clean, fire one clean, fire two clean, fire two clean, etc, fire three clean, each to thier own specific run in procedure, it's common that many new shooters buy a good gun and fire several boxes through it without any cleaning, then wonder why the rifle is a dog shooting 3" - 4" groups, likely copper fouling is very bad, but they can be saved to a point if properly cleaned and re-run in properly, handgun or rifle sme thing.
Good shooting.