Remington Sluggers shoot decent from my old Win 1400 12 ga. & they are cheap! Too bad they changed the copper solids, the old ones shot great out of the gun using a screw-in rifled choke tube – but the new ones hit sideways at 100 yds 50% of the time.
In my son’s 20 ga. the Federal Barnes 3/4 oz. copper slugs shoot great. However, these have now been replaced by 5/8 oz. ones – and of course those don’t shoot nearly as well either. Luckily I just found a small hunting store going out of business that had the 3/4 oz. ones still – and bought every box they had! Now have enough to last another 10 years.