All right I have been attempting to work down a 220 SMK subsonic 300B load. There is all kinds of data online but I can't seem to find one that I can get below 1040 fps or so with what I have to work with. At the time I am kind of limited to Trail Boss, H110 and Lil-Gun with CCI mag primers. My barrel is a Wilson Combat 1/8 10.5" (w pistol gas) with a YHM QD Phantom suppressor. I have had success in getting it slowed down with stable bullet flight but still getting the sonic crack. I just now tried some loads of 9.9 grns of H110 (listed as a min load from my source) at 2.260 COAL. They cycled fine, were stable but no not to quite. What says you INGO 300 BO guys?