The birchwood casey permablue paste is easy.
You just squeeze some on a rag and wipe it over the part to be blued (probably several coats if you went to bare metal like I did), then wait and nuetralize it.
The directions say to wipe the parts off with water after about 10 minutes of being exposed to the chemical, but I always wait overnight (or several hours between coats) and the final thing I do is wipe off with gun oil instead of water. It just seems to give it a darker, shinier result to me.
Just to clarify, I don't oil/nuetralize between coats. I just put another coat of blue on the barrel until you get the color you like, and the last thing I do is oil it down to nuetralize the blueing solution.
Another good cold blue solution (but I didn't need that much) is Brownells Oxpho blue. I personally prefer paste
http://www.brownells.com/gunsmith-tools ... d1108.aspx
[youtube]http://www.youtube.com/watch?v=eQ6LNhp9pfs[/youtube]
Cold blueing is a lot easier than hot blueing
[youtube]http://www.youtube.com/watch?v=f_tvVAt8LPo[/youtube]