Will a phosphor bronze brush wear away my chambers?

Shooting technical advice
MIKE GEORGE
Most phosphor bronze brushes are a relatively tight fit in the barrel, but not so tight in the chamber, so the danger is pretty minimal.

For cleaning chambers you can get a soft brass chamber brush.

If you clean your gun after every shooting session, vigorous to-and-fro scrubbing with a phosphor bronze brush shouldn’t be necessary.

The brushes also soften with use, so an old, well ‘run in’ brush will be kinder to chamber and barrel walls than a new one.

Personally, rather than using a ‘to and fro’ scrubbing motion with the brush, I tend to pass it through the barrels from breech to muzzles with a screwing motion, allowing it to exit the muzzles before withdrawing it.

This seems to be quite effective.