I measured the walls 3 & 1/2" from the breech end on my 10 ga. (1881)it measures .160....it was reproofed after 1950 it's marked Nitro, 4 tons, 1 & 1/2 oz, 3 & 1/2".
It might not hurt it but I don't shoot 10 guage factory ammo out of it.