Having stopped 'smithing at the end of 2021, I have seen lots of Rem 700's come through my shop, most for truing and blueprinting, handle realignment and re-barreling. My observations over the years, even with RR serial numbers, they started losing quality in just 2 years when they dropped the cast followers for the pressed steel versions.
The bolt handles started being misaligned about 2017, talking to our distributor here gave no information as to why or warranty issues.
From 2015, actions were good alignment wise, but by 2017/18 they were in need of serious re-working, the lugs were far from even and everything from there needed work to true them up. RR actions from late 2018 were very good from the centreline, somehow the machining was far more precise, but the bolts were horrible, so the majority of my builds had PT&G one piece bolts installed. I had 2 rifles, both SPS 7-08's, that had the centreline of the bore more than .050" off from the outside of the barrel and the chambers were crooked by the same amount…lucky they were being re-barreled anyway.
The best REM 700's that I kept for myself are S serial numbered. Funny thing, I only have 1 blued model, my BDL in 17 REM from 1980.
Cheers.