Jim/OH,
I have used the same forumla that you use and it seems that people get up set with the peroxide in the mixture.
My math skills are not what they should be but:
Hydrogen peroxide is a 3% solution, with 97% being water.
70% Isoproply alcohol is 30% water as the inactive ingredient.
Murphy Oil Soap, Pure Vegtable, which they do not list the ingedients, has to be some water there some place.
Just how much percentage is the equally mixed 1/3 proportions of the 3 ingedients actually pure hydrogen peroxide and how long is hydrogen peroxide in contact with the metal in the barrel, a couple of seconds?
Seems like a lot of worry for nothing to me. I would be more worried what is in the tap water that you are getting on you, espcecially with the boil notices on some tap water.
RDE