I've realized, the best way to delead a pistol barrel is to shoot FMJ

That just flattens it out and polishes it so it is harder to see.

Shooting the lead out has resulted in shock and surprise when you blow a ring or bulge in the barrel.

People have done this for years, then one time they shoot a little more then usual or the bullet metal composition has changed and there's just a little too much leading.

When fired the jacketed bullet has to push most of the lead in front of the bullet similar to how a boat pushes a bow wave.
Push too hard or too fast and the pressures soar.  This can ring or bulge the barrel.

Another little surprise is that the jacket bullet rides over some of the lead and "irons" it onto the bore.
This is similar to a lead plating and is hard to see.
The surprise comes when a flake of the thin leading comes off exposing a nice pit in the barrel caused by fouling and moisture infiltrating under the thin plating of lead.

De-leading a barrel is not rocket science.   You can use a Lewis Lead Remover kit from Brownell's or buy some REAL 100% copper Chore Boy pot scrubber pads, peel a strand or two off and wrap around a used bore brush.

The Lewis kit should be owned by all revolver shooters even if you never shoot lead.
The kit includes a special cleaning head that removes lead, carbon, and copper jacket material off the critical forcing cone in the rear of the barrel.
It was a build up of carbon and copper that contributed to the cracking of S&W "K" frame revolver forcing cones.

You see firearms with bulged or ringed barrels and people just assume it was caused by a bullet stuck in the barrel when the real cause may have been "Shooting the lead out".

Agree with dfariswheel even in factory Glock barrels I find a few passes of a dry brass brush and a few patches every 200 rounds or so is all I need to get lead out

Mercury still works.

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