Yes, changing the caliber is possible, and not too difficult of a job, it’s just a matter of unscrewing the front sight, taking out the retaining grub screw that holds the muzzle break, then unscrewing the muzzle break to expose the barrel, then the barrel unscrews by hand, sounds more difficult than it is.
I’m now looking for a .177 barrel for mine.
FX ImpactX, AirArms HFT500, 2xAirArms S200 MK3, Webley Omega, Weihrauch HW95, HW97K, HW98, HW99s, AirArms S200mk3, Gunpower Stealth, Weihrauch HW40pca, HW45 Black Star, Webley Alecto, Crosman 2240, Artemis pp700sa, Swiss Arms SA P1911, Walther CP88 competition, CP99