Here are a couple of pictures of the patterns I shot with the Sumtoy choke. The gun is a 835 with a 24" ported barrel. Ammo was Winchester XR 3" 1 3/4 oz 5 and 6's. Shots were taken at 40 ranged with a rangefinder. First is the 6's.
Here are the 5's.
.670 sumtoy? Both looks good. The 5s will carry more energy incase of misjudged distance
The choke is a .675.
clean it good. get all the oil out of barrel. now alot of times the 835 wants the 31/2 shell because of the big back bore in it.