Cleaning a K31

I finally got a chance to take my new to me swiss k31 to the range for the first time. When i got home I cleaned as per my usual habit. I was using Hoppes #9 and was getting clean patches out. Afterwards i went to grease the barrel as the Swiss did. I couldn't find my regular gun grease so I used some T17 from my muzzleloaders, went to patch out the T17 the next day and apply my regular grease. The first 3 patches through came out black, reapplied the T17 and again had patches come out with black on them today.
I'm a little confused here, what am I missing that my muzzleloader grease and patch lube would keep coming out looking like i never cleaned the barrel before.
Any input would be appreciated

Maybe someone used moly coated bullets at one time. It being a sulphide your natural stuff might contain something that dissolves it, but #9 don't? Just a guess.

Actually I think the grease the Swiss used was for automatic weapons that does contain moly and while they usually don't clean like we normally do. They use the grease while the barrel is still warm and leave it in the barrel and patch it out before shooting again. At least this is my understanding on how the automatic weapons grease is used. So unless they get all the grease out, some may or may not remain in the barrel and gets ironed into the metal when it's shot. The regular grease looks like a regular #2 NGLI grease similar to what is used to do wheel bearings, and general lubrication. The automatic weapons grease is black and does stain clothing and is difficult to wash out. I bought a few of the Swiss STG 57 cleaning kits and does include a couple grease containers of the black grease. Used to use a moly grease on my tractor. But got tired of getting grease stains on my jeans. So now only use Lucas red n tacky. At least it does wash out. Moly coated bullets used to be very popular but some benchrest shooters reported problems with their expensive barrels after using it for awhile. So maybe your muzzle loading grease is effective in getting the moly out. Frank

I've had that happen to rifles as well. much as I can figure, the grease/oil may have loosened carbon deposits you couldn't get the first time around.. I wouldn't worry too much with the k31. the Swiss never used corrosive ammo in them. Interesting about the grease. I've never had that issue with any of my K31s.

If it has moly in the barrel, get some Goop handcleaner, without the grit.