Quoted:
A shooter that can tell the difference in accuracy between a chrome lined and non-lined barrel can zap gnats at 1,000 yards.
Today's chrome lining processes are several orders of magnitude better (and more precise) than when the gun shop lore of "chrome lined barrels aren't accurate" got started.
No, "unlimited-class" benchrest shooters don't use chrome lined barrels. They use stainless steel barrels that were made by hand, by craftsmen who hand-lap the barrel and obsess about the polish on the crown. And these barrels are "shot out" after maybe 1,000 rounds, because the competitor will feel that they aren't as "gnat's eye" accurate after that.
A combat rifle needs to be able to group at about 4MOA out to the effective range of the barrel/round combination, and modern chrome lined barrels will do that until they've had tens of thousands of rounds through them. A civilian's rifle with a chrome lined chamber and bore will stay very accurate, assuming it was made with quality parts and built correctly, and be at least as accurate as the ammo the shooter uses in it (and probably more accurate than the shooter) throughout it's life.
And don't let the discussion about "1/9 needs 55 grain bullets but 1/7 won't shoot them well" confuse you. Both twists will more than adequately stabilize all common .224" diameter bullets. If you shoot ultra-light "varmint-bomb" type bullets loaded to very high velocities, you might have problems with either of these spins being too fast for those fragile bullets - just don't try to send that type of bullet out the bore at 4,000FPS, and you won't have problems because of the rifling rate.
This is simply untrue. In my experience, a chrome lined bore, such as the Noveske I recently sold after a few thousand rounds, is going to be about half as accurate (double the group size) as a similar stainless or otherwise unlined barrel. In fact, I have two stainless barrels with the exact same profile as the Noveske, made in the same FN manufacturing plant, and I can print groups half the size that the Noveske with chrome lining would print. Roughly 0.75 MOA vs 1.5 MOA on average. At 100 yards it's noticeable. At 400 yards, it could be the difference between making a precise shot, or not.
Noveske's stainless barrels are even slightly more accurate than the lighter profile FN stainless barrels mentioned, verging on 0.5 MOA accuracy.