There have been several threads where people have speculated what the "schmutz" is that seems to be found in the small space between the front of the barrel nut and the barrel, as well as in the threads of the barrel and action. This stuff is credited with making the barrels harder to remove than they might have been otherwise.

Some posters have been of the opinion that this schmutz is residue from bead blasting because Savage rifles are finished after they are assembled.

The countervailing point of view is that this is a buildup of bluing salts within the threads because the bluing solution is not adequately rinsed out of the assembled threads when the process is completed.

I recently saw some of this schmutz between the barrel of my relatively new, never disassembled, Model 10 and the inside of the barrel nut. I managed to pick out one piece with a fine needle and look at it under a loupe. It looked like a round shiny metal ball.

Today I disassembled an Axis barrel/receiver that had the same schmutz in it (visible from the outside before disassembly). The stuff looked like teeny tiny round shiny balls of differing diameters.

There was (figuratively) tons of this stuff in the receiver and barrel threads.

Then I had a brilliant (if I say so myself) idea. I took the receiver with the schmutz in it over to my kids' computer that has a computerized microscope on it and took the following pictures.






I'll let each reader decide what you think the schmutz really is. It certainly doesn't look like corrosion to me.
(note: The red you see in the photo is from the red duct tape that I used to line my action wrench.)

If not helpful, I hope this is at least interesting.
Although I posted it in this section it appears to apply to all current Savage rifles with barrel nuts.