I am running a 300 WM, and have for a very long time. I recently moved to a 215 Berger in front of 73.0 H1000, Fed 215m'S. The past two range sessions I saw a fair amount of smoke after the first few rounds. It seemed to subside after that. In load development I had no such issue. I have been told that this is due to unburned powder, but it just started and I have shot it with higher doses of H1000 and lighter bullets (208's & 210's). This A.M. I had 100% humidity, but I can't see that as the issue. Any insight as to why this is occurring? I am going to load a few with H4831 to see if it does it. Thanks for the input.