Most 97's can stand to have the mainspring lightened up a bit. That relieves the heavy upward pressure the hammer puts on the underside of the bolt when operating the gun. The bolt hangs way out there when retracted and that heavy upward pressure makes for some not so smooth operation on them.
On a really worn 97, the receiver raceway on the left rear thin leading edge of the frame gets curled upwards from the bolt being jacked up on the return run into the frame each time by heavy hammer pressure.

The mainspring is best removed and carefully ground to a thinner profile.
(But some just loosen the mainspring attachment screw a tiny bit. That you can get at (just barely) in the assembled shotgun.)

They can stand quite a bit of reduction in power and remain 100% reliable. That provides the shooter w/a much smoother operating action.
The trigger spring itself is very heavy also. But leave it alone,,the action won't benefit from lightening it as the geometry of the trigger is excellent so the trigger pull is right where it should be with the spec trigger spring.


My 1903 mfg TD and a later solid frame are smooth as any pump actions I own. The only part I ever replaced in either is the ejector in the TD model. Ejectors used to be very expensive,but now with the SASS shooters making the guns popular, there are repro ejectors available at fair prices.
Cartridge stops wear out like any other pump or semi auto. The carrier is the locking bolt. A massive piece of steel that pivots up and blocks the bolt into position. They rarely have breaching problems.
I shoot around 6 or 7K rounds a year at skeet through the 97 and have for the last 12 years or so.

I've never had the problem of one tearing my hand up like some people have had unfortunately. It must just be the way the gun is held around the grip. I can see if you have a tendency to leave your grip hand thumb on top of the grip when shooting as some do,,you'd probably get clipped by the bolt most likely.

It's a complicated mechanism inside, filled with parts, springs and things that don't look like they belong in there.
They deserve a complete strip down and cleaning every so often if you shoot them a lot as the cam and race ways collect a lot of dirt and caked up carbon. They benefit from lube but it also makes them collect dirt because of it and their open design.
Fun guns. 120+ y/o design still going strong and people still can't get enough of them.