ill chime in here ive been testing my h&RTopper Model 88 3" chamber full choke with open bead sights.
with slugs and no matter whichbrand 40 yrds is about it.my gun gotgroups at less than 4 in with the rem sluggers in 2 1/2.but not so great with the others...on the other hand winchester makes (000 ought buck rounds for it)i get great groups at 50 yrds and all three shots are in the 4 in circle...in the 3 in mag (000 )4 out of 5 peices of shot were in the circle.the slugs were around 6 bucks for 5 rounds and the (000)buck was about the same price.