I'd to get my ZKK 602 actoin to cycle a little smoother, and stop the cartridges from coming out with a deep scratches every time you eject them.

I've smoothed up the outside of the action, and it was hell rough so I can expect the the internals will be no better.

I'd like to ask on what parts and how I need to work on it to get it smoothed up a bit as far as function, but I don't want to interfere with the headspace so I'd rather not do anything that will affect the bolt lugs like run abrasive paste through it.

When it comes to feeding, where do I need to work and how, to correct any eventual problems? (I haven’t started shooting the rifle and it’s disassembled for bedding)

I realize this might all be fairly vague, but essentially I'm just looking for pointers and any information that might turn out to be helpful in getting this old CZ cycling more smoothly.
I have never attempted to do any feed or action tuning work, but I am careful and work slowly enough not to be too worried about making a mess of it.

My suggestion (which I know from personal experience has worked for me), is to first make up 10 dummy rounds.(No powder, and fired primers.) Then cycle them through the action from the magazine for a total of about 500 openings and closings of the action.

May take a couple or three evenings, but works wonders for smoothness.

And, of course, if you have the time available, 1,000 openings and closings won't hurt the rifle either....just do it using various hand/arm angles so you don't start carpal tunnel syndrome in yourself.