As I said in my post above I have used 2 3/4 inch foster type slugs in an 870 with cantilever scope mount and screw in Remington rifled choke with good results. Some little diference in groups between brands but not much! I stick with the inexpensive Rem Sluggers for this gun.For some reason copper solids group well at 75 yds but not that much better. I use this set up when driving/slow pushing etc. for straight stand hunting I use my Marlin 512P with fully rifled barell & a 3X9 Nikon. Hornady SST's are the best group performers in that weapon,the bonus(for me) with the screw in chokes is the ability to go to a Remington Superfull Turkey choke with minimal varience in POI. I can tell you that set up will flop turkeys and put major leaks in deer!!!