i have made perhaps 100 flights with declared and checked handguns. i just returned from a long distance trip on american airlines and haven’t fully unpacked yet. with no chance for plinking in the forecast this trip i carried all 38sp. if plinking one piece would be 22lr. always two is one, one is none: handguns, ammo, especially non tsa locks. i have also used a plastic ammo box with two locking points when taking a longer ruger single six plus more 22lr ammo for plinking. all goes into a tsa-locked & checked piece of luggage with usual clothes and toiletries. double check that all firearms, mags and speedstrips are fully unloaded, with all ammo in factory boxes (i reinforce with tape). essential for at least two locking points on the handgun case with both locked.
best experiences are with female checkin staff in las vegas: we compare notes about handguns. worst is seattle: we are shunted off to wait almost an hour for antigun tsa staff to interrogate us. most checkin staff don’t care but enough are clearly antigun and question why i need two, let alone one, handguns, and are either afraid or upset to do checkin quietly and efficiently.
i have several nonresident ccw permits, and i always check airline guidance and handgunlaw.us before each trip for updated guidance. never connect through or arrive in a state where having a handgun under any circumstances would be problematic, e.g. ny, nj, ma, hi...