Let's get it out of the way.
Using remake FedArm ammo. Shot tons of it in the past with no issues.

Sig 320 Legion. Put about 150 rounds through it. My son using it so can't speak of any strange noises.

Broke down for cleaning and there is a "ring" about an inch past the chamber. I "feel" a hump when pushing a patch through it. No bulge on the outside of the barrel. Won't brush out.

Figure maybe a jacket on cheap bullets separated?

Already ordered a new barrel. Hopefully drop in fit?

Bulge or jacket? Anyway to remove a jacket separation?

Approx. 200 rounds of FedArm ammo for sale.

Obvious stupid question....bronze brush have any effect??

Have you soaked the area in question with a solvent patch left in place???

Drag a long tipped cotton swab across it. That may give you some info as to the composition.

Any access to a borescope??

Andrew

It's a raised area as opposed to pushed out.

Soaking a patch over it now. Copper solvent.
I'll leave it for awhile.

I believe the ammo you have is copper plated rather than jacketed. Educated guess is the ammo. Can happen for a number of reasons with plated. You should be able to clean up soft plating residue.

Nothing wrong with plated if done right.