On a dog town when it is 85-90*, barrels will not cool down for hours.
We did the water down the barrel thing for years, with two top engineeers as shooting partners. Our rifles were anything from Howa's to 788's, but mostly custom rifles with Hart and Shilen barrels.
After a couple of years, we started putting on he Max Heavy Contour and Unturned blanks. We usually got 3 chambers on a 28-30" barrel that had 6 Inches of straight on the breach end(max heavy varmint contour), and perhaps the same on an unturned blank....none were ruined by water down the barrel. At that time, I was shooting 24,000-26,000 rounds of centerfire a year, hunting partners about the same...we all used water down the barrel. 223's, 6ppc's, 6 BR's all got 10,000 rounds+ on a barrel with multiple chambers, they were usaully replaced due the fact that copper fouling started accumulating faster and meant more cleaning time and less shooting.
4 dry patches down the barrel after water extened shooting strings vs just letting the fouling accumulate in the barrel if you were just air cooling the barrel.
I am still shooting some of those very same barrels today, and they still shooting groups less than .385.
If you are shooting at the rifle range for fun and hate shooting your barrel red hot or shooting ground squirrels/p. dogs, treat yourself to a standard rifle cradle(tipton, decker) attach a rod caddy that holds two rods(
www.sinclairintl.com), one for the cleaning brush and the other with a punch jag on it(for the caliber). With a water bottle with a plastic tube attached to it that feeds water into the back of your rod guide, you will cool your barrel, dry patch the barrel out, dry patch the chamber, and be back to shooting in 3 minutes tops.
Any questions?