Using the shoot one clean one you can see the fouling stop...usually 2nd or 3rd round.
Does this matter?
You might laugh at me here, but for years I used to think a lot of things I did mattered.
The more I focused on what I did and how I did it the better I shot....My rifles usually shot a fair bit better than most other guys equipment seemed capable of....Then I retired and got to the point where helping folks with their shooting mattered more than winning....I was surprised to learn their equipment and reloads were often as good as mine! All that crap I fussed over in the loading room...was pretty much worthless.
It was the tens of thousands of rounds I was sending that made "my rifles shoot".
I preach a different sermon these days...I don't talk about single digit runout or even suggest that Savage sucks any more....(
All you will hear from me these days is "send more rounds down range" or "square up your trigger pull"....That sort of thing....truth is nothing else really matters.
It is also true that I enjoy shooting more now than I ever have.