Rust in the barrel. Big deal?

[palouse]

I am redoing an old 870 I was given. I have found that there is some rust that caused mild pitting on the outside of the receiver and a little on the outside of the barrel. After cleaning out the dirt in the barrel, it is now obvious that there is rust inside the barrel. I am guessing that this will also have some mild pitting. It appears that one side of the barrel still has a smooth bore, while the right (the down side) has a bit of an irregular surface. Is this a big deal? Should I fire a few rounds through it and see what changes? Should I scrub away for a couple weeks? I would like to decide whether it is worth me scrubbing at this or if I should just plan on buying another barrel? FWIW, I plan on using this gun for ducks and turkeys and won't be going out for trap shooter of the year.
Thanks,
Kevin

 

[ArmedBear]

Hmmm...

If you want to use it for ducks, is it rated for steel shot? Is it a 3" receiver?

Otherwise, clean it up with something like Kroil or some other rust removal product. See how it looks.

Also, 870 barrels are available, and they're not too expensive.

 

[palouse]

Thanks for the reply.

It is an Express barrel made in Aug. '94 according to the stamp on the barrel. I would assume that it is rated for steel although the Remchoke in the barrel may not be. When, if ever, were Expresses manufactured that were not approved for steel? It is chambered for 3" shells. I don't think that the pitting is anything more than minimal. I just don't know how important it is to have an absolutely slick barrel.

Thanks again,
K