Updated 4/6 with warmer day pic and details. Pretty cold and windy on the first day, 20mph and 48 degrees. Not the best weather but I wanted to try out the new SSX tube. I cleaned the bore prior to the session and swabbed it out between shots. Shot a couple lead #4's just to check POA/POI at 20 yards got about 8" of coverage at that range and was dead on. I then shot (all 3 1/2") Hevi 13 #6, Hevi 13 MagBlends, Heavyweight Federal #7, and LongBeard XR #5. Hevi 13 #6 and Heavyweight Federal #7 both shot pretty well, 186 in 10" and 194 in 10" both had pretty good coverage in 20" as well but the H13 #6 continues to outperform others. I counted up the last two rounds I shot that shell and with Roberts .660 and this .643 SSX both of them were almost 90% patterns in 20 inches. Here are the pics of both shots. Will shoot them again when it really warms up and see what it can do . The MagBlends and LongBeard XR did not shoot too well on cold day, shooting 149 and 135 in 10" respectively. Given I've now shot the MagBlend through Indian Creek (.665 and .675), Roberts .660, and SSX .643 all with pretty poor results I'm going to go ahead and take them out of the running, my gun simply doesn't like them for some reason.
Today 4/6 I shot again with LongBeard XR #5's at 60 degrees calm wind and the SSX .643. Definitely improved significantly over the colder day listed above. On a similar weather day I shot the LongBeard 5's with my Rob Roberts .660 choke and got 197 in 10" so both of these chokes will perform well with that load. Both pics now attached.