TE_Dirtracer

If you purchase a 45-50 caliber sabot it will hold either a .451 or a .452 sabot, the only difference will be that the overall package as it goes down the barrel will be slightly larger than the other. And believe me that .001 canseem awful big sometimes.

Randy's suggestion of the MMP HPH-24 is the thinnest sabot that they make and is the one that I use in my Remingtons, Thompsons, and A7H's. I always considered these to be very tight barrels. I load Nosler .451's and Hornady's .452 with these sabots. You can purchase them on line from several places or even from MMP direct

http://www.mmpsabots.com/

The Harvester's t7 indicated will work also and are used by many people.

There are some new Thompsons out there that the barrels are so tight that you may not get either of these sabots/bullet combinations down. I do not have enough information/eperiance with the Encore to make that call though.

Good luck