I clean whether I fire 1 or 100. I do load development using a cold clean barrel too. I can keep it consistent at clean and first round impacts are always where I put them. Couldn't give a toss what it does after 20 
I used to be in the not to clean camp and the next bullet will clear it until I had moisture in the barrel after a downpour only to find the next half a dozen rounds were off after a couple of patches were put through it
I used to be in the not to clean camp and the next bullet will clear it until I had moisture in the barrel after a downpour only to find the next half a dozen rounds were off after a couple of patches were put through it