ORIGINAL: superstrutter
The hevi 13's don't pattern well at all in my setup( 870 SPS-T). They didn't do well in my other gun either. The Rem. hevi shot magnums are awesome in both of my guns. The high velocity does pretty good also, but not as well as the mags. I use the 3 1/2 inch 5 shot. I also use the jellyhead choke. I won't use hevi 13's, but I'm sure they do well in some guns.
Superstrutter beat me to it! The hevi 13's patterned terrible in my 870 SPS-T as well. I was getting bad patterns with the Hevi 13's at 30 yards with a Primos Jellyhead. I switched over to the Federals and haven't looked back. I am confident out to 50 yards with the Federals. Of course patterning is something you have to do and they may pattern wonderfully in your gun. Best of luck!