Yo Lucho,
Yes, the bench and top level bench-shooting are necessary to be able to differentiate ammo quality as a function of accuracy on paper but I dont agree with your listed issues that follow:
1. Consistency of ammo (velocity consistency, concentricity, bullet shape...)
2. Barrel quality (smoothness, crown, quality of chamber....)
3. Rifle quality (how the barrel is put together, bedding....)
From years of shooting SB Silhouette and shooting groups at 100 yards and meters Id say that MV variation is important but so is bullet alignment to the bore when we are concerned about accuracy at turkey and ram distance. My top three ammo/rifle issues, in order of perceived importance, that predict accuracy are:
1. Bullet-to-bore concentricity without that no amount of money thrown at ammo will help accuracy
2. Bullet-to-bore concentricity without that no amount of money thrown at ammo will help accuracy
3. Bullet-to-bore concentricity without that no amount of money thrown at ammo will help accuracy
A little tongue-in-check like the answer to the old real estate question, What determines the price of a piece of property?, location, location and location.
From years of shooting, designing reamers, rifles, pistols and bullets I would suggest that bullet alignment to the bore when the gas pressure obdurates the back of the bullet is tantamount to the attainment of high levels of accuracy with 22LR ammo. That means that concentricity of bullet to bore is more important than any other factor as long as MV variation is below 50 fps. As with all parameters used in the optimization process, if we drive one factor way out of range we get a first order effect when in fact within the range it is a second order effect. That statement assumes that we are not hindered by the trigger, shooter, rest, etc.; variables we can control. For match ammo I look for 30 fps or less for a 50 shot string over an Ohler chronograph with ½ MOA accuracy under ideal conditions like we often get on Tuesday nights after about 7 PM at SRGC.
A simple test to see if there is potential for accuracy is to carefully chamber a round and extract it while trying not to scratch the bullet. Next, use a magnifying glass to check for consistent engraving on the cylindrical portion of the bullet behind the nose ogive. There should be engraving along its complete length that looks the same all the way around the bullet.
As an example from years past, my first SB Hunter Rifle was a Kimber. Those rifles were known to be accurate, but were also known to be finicky about ammo. The Kimber had a very sloppy chamber in that the bullets did not engrave at all. That is why it was so finicky about which ammo would shoot well in it. Fast forward to a few years ago when I was shooting a Lilja barreled Finnfire with the tight Lilja chamber. That barrel would shoot anything well. All of the ammo tested in it had symmetric engraving on the shank portion of the bullet between the case mouth and nose ogive.
I have had, in the past, ammo that had good MV consistency, in the 30 fps range, but would not shoot well, over 1 MOA, in my Anschutz 1700 FW. That ammo had bullets that were not tight in the case. The bullets could be spun and wobbled a bit in the case. Yet one more example of ammo that would shoot well in a tight chamber, the Lilja, and not shoot well in the Anschutz factory chamber.
Certainly quality gunsmithing is a must if one is to even get to the point of deciding which ammo will shoot the best in their rifles. Barrels are also important. They must have consistent bore/grooved dimensions all the way down the tube. It there are tight or loose spots in the barrel kiss accuracy good by.
