Please consider that:
"Rechambering" means reaming out the chamber area of a barrel only.
"Reboring & re-rifling(usually)" means reaming out the bore area of a barrel only, then cutting rifling into the newly bored barrel.
"Rebarreling" means changing out the entire barrel for another.
FWIW
barrels get rechambered, not rifles
barrels get rebored & rerifled, not rifles
barrels get rebored & rerifled & rechambered, not rifles
rifles get rebarreled & chambered.
If someone simply rechambers "a" barrel with a .264 Win Mag reamer, AND the bore is anything other than .264"/6.5mm, the result will not be a .264 Win Mag rifle.
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