Be sure to take the trigger out of the trigger housing and clean all the crud out that accumulates over the years underneath the trigger. Without knowing it, it leaves you with a hair trigger that can go off at the slightest touch. I worked on these for a number of years. People would come in complaining that the gun would go off when they pumped it hard.
That can be very dangerous, to say the least.
They are a great old gun. I grew up shooting my uncle's for ducks.
Many fond memories about hunting with a 97.
williek