I have loaded the sst in the 54 thunderhawk without any problems,but I do use the harvester red 54 sabot.My other t/c they will just not go down the barrel after the first shot. I also found the they shoot very well at the 50 yard target ,but can't seem to get them any better then 5 inch group at the 100.
I use the noslers 300 grain full partition sabot they load like silk no stater hammer needed