How long should I wait between shoots when testing my load? I have heard that some guys use water and buckets to cool there barrel how it this performed? Right now I shoot 5 rounds and wait 10 min then shoot 5 more. I think this is fine BUT. It is realy only the first shot I am worried about. It is my observation that the first round it POA - POI but then as my barrel heats and the rounds start to fall on each other the group will shift down and left 3". I know why this happens but is it effecting my load testing? I just am not sure? If the first round and the second are 3" apart but after the second round the rifle groups what do I do If I have to make a QUICK follow up shot? I will be 3" off at 100yds now compound that by 7 or 800yds and you have a miss.