a little tip about screw in chokes: Treat them like your breach plug in your muzzleloader, clean them regularly and always use lube on the threads... My 11-87 has the same system as the 870's and i've never had one sieze, i shoot lots of 3 1/2" BB, BBB,T etc through it and almost always had the factory FULL STEEL OR LEAD tube in...canadian-ice said:I have found steel to work just fine once I started using the right chokes. Pretty much anything BB or larger, patterns best for me using i/c. Some smaller shot sizes I can get away with modified and can a get a pretty deadly pattern with #4 shot for ducks over decoys. I even ended up seizing a full choke into my 870 after much shooting with steel BB's for geese. I don't recommend using any choke tighter than modified when shooting steel.