Rust in my 870? or not

[TNP]

I recently cleaned my remington 870 police magnum 18.5" and when I ran a patch wet with break-free clp a brown residue came out with it. Is there a chance that this is rust? It should also be noted that I used hoppe's no 9 solvent before I used that patch, let it sit for a few minutes (hoppes no 9), ran a copper brush, then a dry patch (no brown residue just black gunk), then 10x with a bore snake (no brown residue). The brown residue only came out when I ran the oil patch. The inside of the bore looks like a mirror, how can I tell if this is rust or just dryed up hoppes no 9 residue? It should be noted that I bought this used as a police trade-in but this problem just recently started to occur.

[BigDogatPlay]

I doubt it's rust. After a light coating of Break Free dry patches always come out with some discoloration. Part of it is the Break Free and part of it is residual of the solvent.

For what it's worth you don't have to bathe a patch in solvent to run the bore on a shotgun. Many top level shooters I know run just a tiny bit of Break Free or similar on a bore snake and call it done. I only use solvent on powder fouling in the action.

[mikey357]

I recently cleaned my remington 870 police magnum 18.5" and when I ran a patch wet with break-free clp a brown residue came out with it. Is there a chance that this is rust? It should also be noted that I used hoppe's no 9 solvent before I used that patch, let it sit for a few minutes (hoppes no 9), ran a copper brush, then a dry patch (no brown residue just black gunk), then 10x with a bore snake (no brown residue). The brown residue only came out when I ran the oil patch. The inside of the bore looks like a mirror, how can I tell if this is rust or just dryed up hoppes no 9 residue? It should be noted that I bought this used as a police trade-in but this problem just recently started to occur.

I use Flitz as a rust indicator in suspected areas where I cannot get a direct observation.

[p2rider426]

I doubt it's rust. After a light coating of Break Free dry patches always come out with some discoloration. Part of it is the Break Free and part of it is residual of the solvent.

For what it's worth you don't have to bathe a patch in solvent to run the bore on a shotgun. Many top level shooters I know run just a tiny bit of Break Free or similar on a bore snake and call it done. I only use solvent on powder fouling in the action.

+1. It would take some pretty harsh conditions to rust a bore of a shotgun before any external parts. I've taken my 1965 Remington 1100 with delicate bluing on shooting trips to the snow and even though I took great care to keep it rubbed down with oil I ended up with a very small surface rust spot on the outside of my barrel. I didn't even clean the bore until about a month or two after being exposed to those harsh conditions and it was absolutely spotless, even though it wasn't kept coated with oil like the exterior of the gun.

[TNP]

Thank you! Your responses definitely provide me with a lot of peace of mind. And Mikey I'll definitely look into that Flitz.

[mikey357]

Thank you! Your responses definitely provide me with a lot of peace of mind. And Mikey I'll definitely look into that Flitz.

I had some fouling in the bore that would not come out. I thought it could have been rust so I used some flitz and it came back clean. Repeated passes with bore solvent just started to take some of that stuff out so Im guessing its plastic wadding that got the bore streaky. Im thinking a cyclone stainless brush will be the ticket to get that stuff out.

[jyo]

I find that Remington's "Rem-Clean" takes that plastic stuff right off your shotgun bore---put some on a brush and run it thru---let it sit for 3-5 minutes and use a clean patch to remove---run a clean brush with BreakFree CLP on it---DONE!

[Barbarossa]

I just use WD-40 or RemOil and a bore snake.

It's a smooth bore, so note sure I understand the fouling thing.