Dillinger's recommended barrel break-in is about as sensible as it gets. I've had acquaintances drive me nutz with days and days of single and multiple shots out of their new rifle barrels. When they should be shooting, instead they are stinking up the rifle shack with a bottle of Hoppe's #9.
At risk of appearing facetious, I'm not entirely certain what good all this barrel cleaning does for people's rifles. The better marksmen I shoot with always outshoot the poorer ones; and, so far, no amount of barrel break-in has changed that basic reality.
Do you need to clean and reasonably shoot-in a new rifle barrel? I think that to some extent you do. (If nothing else it, 'irons out' the new rifling and cleans up any residue left behind by the manufacturing process.) The only question I've ever had is how much is enough?
I'll suggest this: If you're a benchrest shooter, then, a more rigorous barrel break-in regimen might be appropriate. If you're a hunter or combat shooter, I think a more modest break-in should be adequate.
When I was a young man I never broke in my new rifle barrels; and, at matches, the only shooters who ever beat me were the guys with heavy bull barrels on their rifles. Rifle for rifle I could always outshoot anyone else on the line.
This has lead me to the opinion that a properly bedded barrel, a heavier barrel, a barrel with better harmonics, or a better fitting stock is worth a whole lot more than some of these ridiculous barrel break-in regimens I've watched modern riflemen go through in recent years.
Did somebody say; 'Wolf ammo' and, 'accuracy' in the same sentence? Too funny! I'd suggest that you give your new rifle a good cleaning before you shoot it the first time. Then clean out the barrel again after the next 3 or 4 single shots. Do some more light shooting, and - that same day - give the barrel (and action) another good cleaning.
After that initial range session, be sure to clean the rifle every time you take it out for, at least, the next year. Every so often remember to use a copper solvent on that barrel, too. If your experience is anything like my own you'll have more trouble developing an accurate round to shoot in that new rifle than you ever will with any protracted bench shooting regimen of barrel break-in.
For whatever it's worth: I do use Flitz Polish on my pistol barrels. After almost 5 years of regular use, the only thing that's become more inaccurate is the shooter and not the barrel.
Flitz swears, up and down, in their literature that their polish is not abrasive. I have noticed that Flitz and Iosso Bore Cleaner seem to be identical cleaners; Iosso, also, states that their bore cleaner is completely non-abrasive.
(Gee, I sure hope so because I've been regularly using it on all of my bores for many years now.)