I have the T/C Enore 12ga rifled slug barrel.. I put a 1x Nikon scope on it, as I have been having a lot of trouble with open sights on long guns lately. I have had it a couple of years, but no deer with it yet.... So far I have tried 3 types of sabot slugs in it
The first is a discontinued 1oz 2 3/4" BRI slug from Federal, #F127SS, which I still have 1 1/2 cases of that I had bought specifically for my NEF Tracker II. They shoot ok in the T/C. This year I tried 2 different ones. The 2 3/4" 300gr SST slug @ 2000fps , and the FUSION sabot slug, #f154FS2, 7/8oz @ 1600fps.
Just for reference, I also shoot 22LR, 209x50ML, 338Federal, and 256 Win from this same Encore rifle frame.
The Hornady Fusions shot REALLY well, and adjusted precisely to scope adjustments. HOWEVER, please note that part way through my trial for this load I realized that EVERY primer had been pierced. I was not thinking clearly regarding this, or I would have kept the shells to send to Hornady.......but it was obvious to me that the pressure level of this load was far too high for my gun. I would conjecture that the load was primarily designed with bolt guns in mind. I immediately stopped shooting them.
The 2 3/4" Fusion Sabot Slug, 7/8 oz, 1600fps was less than $8/box at Dick's sporting Goods, and did shoot reasonably well for me. Better than the Federal F127SS's did. I got a 1" 3 shot group, 2" 4 shot group with these at 50yds, set to 1.5" high for a theoretical 105yd zero. Regretably, I did not have range time to shoot at 100yds, but hope to at another range session soon. After this target was shot, I did stop back at Dick's and buy 10 more boxes of the same lot to have on hand. I did carry this load hunting, but not until my 2nd of 3 days out, with an embarrassing smoothbore miss my 1st day [that was the end of my delusions of tradition......]

, and so I never got another chance at a shot using the Encore. Next season will be different, maybe.
I am posting the target for the Fusion sabot slugs. The 2 lower holes are my 1st 2 rounds, the 3 high, left after a scope adjustment, the 4 rounds a little right of center averaging 2", 1.5" high are my final group before going out to the field.
I was very pleased with the Fusion slugs, as I said , they were less than $8/box. They sighted in very easily, just like my 209x50 barrel did, in this case using only 9 rounds.
I would be very interested if you get/have this barrel what your results might be also, particularly were you to try the 2 3/4" Fusion slugs.