Coyotes are not that tough. If you don't want to waste money buying a bunch of fancy shells and chokes you don't need, then just shoot them with your turkey loads. The #4 Longbeards will kill them dead as a hammer if you shoot straight. I have killed several with plain #6 lead unplated shot, one shot kills. The ammo and choke makers want you to believe coyotes are "tough" to penetrate, they are not. The biggest mistake most people make is choosing shot to large and missing the vitals due to holes in the pattern. #4 Buck would be fine as well and will not hurt your choke. #2 lead shot would make a good choice also.