Brian49....What exactly is "brush and dry patch" ? I hope you are using lots of solvent when you brush....never run a dry brush through a dry boar. I am pretty sure you know this, but just making sure. I just re read your post...."I usually don't use solvents I just clean off the high spots".....OMG...I would stronngly sugjest you change your ways!!!!
Winmag.....I am the exact oppiset.....I clean when the bbl is still hot.....they clean up much faster. If they are really hot I don't let the solvent sit for too long.......it's when the harsh chemicals start to dry up is when they start causing problems. As a matter of fact, I use a Black & Decker heat gun to warm up a cold bbl before I clean.
As far as the origonal question. yes, I clean between different powders, or bullets, or...whatever. I want to controle all of the variables. I also shoot at least one fouling shot. I clean them CLEAN!!!!
I dont wait for them to cool before I clean, I wait for them to cool between shots. And I never ''heat em up beyond ambient temp'' for anything. That being said, it gets up to the hundred and teens in August in Hells Canyon, where I hunt bear, and its been as cold as -teens where I elk hunt. I shoot in all conditions because I hunt in all conditions. Ambient temp or as close to it as possible is always best IMO for real data, and prolonged bbl life. I NEVER shoot so many rounds that my bbl gets hot, and keep going. I know that WILL shorten bbl life.
On another issue, I always start with a clean bore. And I will certainly clean thuroghly before I swich brands, ie; Hornady, vs Nosler or whatever. I f I shoot both on the same day at the range.
Proper bbl break in is crucial IMO, and takes time to do properly. I thought I was more anal than anyone till I read some other folks' tecniques. Namely, MontanaRiflemans way. I plan to try his tecnique next. But once the bbl is broke in, I have proven to myself that longer strings are ok, as long as the bbl does not get hot. I hate to belive this, but the theory has merrit, and holds water.
Not that it works on all rifles. I had a 223wssm that required a rediculous amount of scrubbing every 10 rounds or less, or it would foul so bad that a sub moa rifle would shoot almost 1 3/4'' at 100yds. But for most of my rifles, the less cleaning, and longer strings(on a cool bbl) works better. But I still scrub the snot out of all my guns, when I get home, even if its only been fired a couple times. I cant go to bed knowing I have a dirty gun.