You may have one of those guns where you will have to decide if it likes a clean or dirty barrel. I sight all mine in with a fouled barrel. Just like tonight as I load for Sat. morning I will shoot just a 15 grain load of powder (no bullet) thru mine to dirty the barrel then load it to hunt. I do this with both my Hawkins and my wife's wolf before loading to hunt. Go thru the same process at the range when sighting them in before season. Reason as both our guns like a fouled barrel. But on the other side have owned a couple that like clean barrels. Get 3 shots then thows em. Can't help ya much with the 777, my guns and I don't like it. There is a lot of good advise and opinions on here, but in the end you need to get some range time and figure your gun out.