Wife inherited a 1908 Colt .380 hammerless and I had to totally disassemble to degunk it. Guns that old that have been neglected can be ruined.
***Guns that old that have been neglected can be ruined. ***
I bought a nice pre-WWII Czech .32 pistol a few years ago. It was perfect outside and had only been fired once when bought new back in the 1930s.
The barrel was ruined as corrosive ammo was used and the gun never cleaned.
I almost lost a barrel on my brand new Browning Hi-Power when I fired it with surplus Nazi ammo I bought back in 1968.
Luckily I realized the bore was RUSTED! BAD! from that one shooting session and cleaned it. It still had small pits from the ammo. I felt sick!
Years ago I bought an almost perfect 03-A3. The bore was almost perfect but you could barely make out pitting as it obviously had been fired with corrosive ammo and probably cleaned a few days later. It was still super accurate.