Remington produces barrels in a variety of styles, choke sizes, finishes and lengths depending on demand. They record the date the barrels were produced and rollmark them with a code that identifies that date on the left side of the barrel.
There are also proofmarks recorded and stamped on the barrel. Whomever proofs that barrel may have a specific way only known to him or Remington alone that will further identify the barrel. Their time of employment with REM is a great timeline.
They produce light contoured barrels for instance, that were never used for Police Magnums with markings of their own produced in a different department, as you already know Police Magnums are produced in a separate part of the plant for greater QC. Cut one of those down to size and you'll easily be proven wrong.
There are many other variables that can be considered in establishing when a particular barrel was made and what length a barrel was cut to before it left the factory.
The stamps used to mark the barrels may eventually need to be replaced, the tooling may be differnt from then and now, from one barrel batch to the next and that is plenty to date a barrel.
It may not be a big deal for a machinist to cut a barrel down to size in a very professional way, but to have all the variables coincide just to be sure that it cannot be proven a cut down barrel, is a very long shot and near impossible proposition.
If you unknowingly chose a light contoured barrel for your chop job, even if it has the correct timeline markings, light contoured barrels were never used for Police Magnums or any 14" barrels.
In short words, believe me, Remington knows exactly which barrel was made when, what size and for which gun and to whom, or where it was shipped when it left the factory. They don't even need the serial number.
With today's forensic technology and the knowledge to prove you wrong, I wouldn't mess with cutting barrels to less than the ACT allows.
It would also be a very bad thing to cut a barrel down and later sell it to an unsuspecting soul who believes he bought a bonified REM barrel only to find himself in deep mud.
