Here is what one of my revolvers looks like after 100+ cast loads through it,
It seemed to get to that point and simply level out. I have cleaned it once since that picture and probably have close to 250 through it now, and it looks about the same as above.
Now this is what your not wanting to see,
or even this,
Like mentioned above though, it only takes a few minutes to remove using the copper chore boy wrapped around a bronze brush. Add in a little Kroil and let it work for a half hour prior and go to town.
That said the best way to NOT see it is to simply try your best to avoid it. This might mean you need to slug your barrel, (easiest way to know what you need to size your bullets too,) you might need to strengthen your alloy depending on what your looking at pouring for. Do a little research on pressures and how it effects the alloy, and what hardness, or alloy works best at what pressures.
Lube is next in line. Most loads can easily get by using plain ol mule snot, (Alox). It is a bit messy and slow, but it does indeed work very well for most applications. It is especially good when using the push through sizer like Lee makes. Lube once before sizing, and once after and once dry your good to go.
Some of the higher pressure and velocity loads however benefit form a bit more substantial lube such as some of the commercial or home made versions.
With the lubes I HIGHLY suggest looking up White Label Lubes. If your simply looking to tumble lube get a jug of the Xlox 45/45/10 blend. It will go on thin, dry fast, and lube just as well as the straight version of Alox.
If you want to pan lube, pick up some of his stick or slab in 50-50, BAC, or Carnuba Red depending on just how hard you want to push things. Use from slow to fast in the order I listed them. They make remarkable lubes and price them at a point that you can hardly make it yourself for what they cost ready to use.
If you have some clip on wheel weights, or range scrap, either of those can be used for most handgun loads in plain form or alloyed softer or harder depending on what your shooting. Rotometals would be the best place to shop if you simply want to harden up something you already have on hand. They have a formula listed to help out when adding hardness to your alloy, and if that isn't up to snuff, there is an alloy calculator loaded up over on Castboolits that is a real nice little spreadsheet. It has most alloys already in it and you simply go from there to blend up what you need or want. While it isn't down to the last molecule accurate, it is plenty close enough for blending up repeatable alloy.
