Isopropyl Alcohol is NOT MOSTLY WATER. The other way around. Yes, it has water in it- about 8%, but that evaporates easily with the alcohol.
If You worry about those things, go to the hardware store and buy a quart can of Denatured alcohol,which is closer to 100%( it has additives so people don't drink it.)
Both alcohols work fine. The purpose of flushing- not just running a dampened patch down the barrel, or a dampened "swab" is to dissolve any grease, or oil in the breech of the barrel, and if one exists, in the powder chamber, and the small holes that connect the chamber or breech to the TH on flintlocks, or to the base of the nipple on percussion locks. Flush the barrel with some alcohol- the amount varies with caliber, and barrel length somewhat---- and pour the mix out the muzzle. NOW, run a drying patch down the barrel to gather any remaining oil and alcohol, before you load that first powder charge. Don't be afraid to blow down the barrel to push the last of the fumes Out of that flash channel, either. :thumbsup:
I have also used Alcohol as a Cleaning fluid between shots when shooting in sub-freezing temperatures. But, I always follow the damp patch ( with alcohol) with a dry patch to get any remaining alcohol out of the barrel before re-loading the barrel with the next charge. :hmm:
Some people mix alcohol in their water based cleaning fluids, to keep the water from freezing in the barrel. That works in conditions where you are going to fire the next shot fairly soon, but will not protect the bore from rusting where the PRB touches the rifling if you leave a patch dampened with any water in subfreezing temperatures long enough for the water and alcohol to evaporate( as in hunting.) That is why I use straight alcohol to dampen patches, or OIL only, to dampen patches for sub-freezing hunting conditions.
There are a number of oils, both vegetable based, and synthetics, that work well down to below zero Degrees F. A thin mix of beeswax, and vegetable oil will keep the patch soft enough to run down the barrel, and oil the barrel to fight condensation in freezing temperatures.