I have had exceptional good luck with Federal Barnes Expanders - gotquite a supply about 3-4 years ago on sale, so I don't know if they are still available.I also tried Lightfields(?) but did not hold groups past 50 yds. It's a great combo. I just took my Encore out Monday night - I didn't use it last year due to rifles being allowed in my part of NY, so I used my Marlin 44 Leveraction. I think I am going to pay alittle more attention the the Encore this year.
Hope you have as good of luck as I have with mine !