That bullet comes undersized. Atypical 45/50 bullet will be .451/.452. Not so with the SSBs. Mine usually measures in the .449 neighborhood. My last purchase of SSBs still contained their use of Harvester plastic sabots.... Harvester commonly regarded in ML circles as having the easiest-loading plastic sabots.

Also... let me pass you another reminder that Hornady/Knight plastic sabotswere generally regarded asthe thickest .... those being white in color for the 54. It's been two years since I tested 54-cal plastic sabots, so things may of changed since.

Further evidence that Hornady plastic are thicker than MMP can be found inside the newer distributed T/C packaged sabot/bullets. The complaints that the new Hornady plastic sabots are more difficult to load than the older MMPs have produced a mountain of headaches for T/C Inc.