My grandpa's stevens single shot 12ga. don't know the year but its old as hell and a winchester model 1890 22 pump thats a tac driver and last winchester model 1897 12ga pump..... My dad told me before he died to never let these guns out of the family.... But my oldest weapons are axe heads and arrow heads, I would say Miami Indians used, "I know there not guns...."
Just purchased what is now my "oldest gun".
Single barrel muzzle loading shotgun. Made in Birmingham, England. The maker is listed in historical records as being in the gun making business between 1836 and 1857. Barrel has Birmingham proof marks consistant with that period. It's had some refinishing but it's a shooter, not a museum piece. Bought it for shooting BP muzzleloading trap. Widow of owner said it was used to win national championship in that sport, had papers and photo to prove it.
I've got matching Cooey .410 and .22 bolt action, single shot long guns from the late 40's that were my dad's first guns. My Mosin is "only" from '42, but I recently inherited a 16ga FN double-barrel shotgun made between 1908 and 1911 by the markings.
I have never really tracked the age of my firearms - however I have a 1891 Mosin (not 91/30) and several old Mausers from various countries, some I remember as being pre WW-2, not sure if pre WW-1.
I have a Springfield Trapdoor .45-70 made in 1883 that has been used in BPCR competition and placed in the top 10 one year in the main shoot in New Mexico. It is shoot often out to 500 yards. I can't see good enough any more to do 1000 yards. Scoped it will still knock steel at a 1000 yards.
Well my oldest would be my 1944 M44 Mosin, but my Browning A5 would probably be second on the list. I don't have that much older stuff. Even though I do like the older war time rifles.