I'm not sure how cutting off the choke is going to help?
The pellets will be undersized by the tight spot at the breech and then maybe unstable as they go along the rest of the barrel. So if I cut off the choke they may leave the muzzle unstable. How will that help?
Out of interest ...
What group size edge to edge is acceptable rested at 55 yards. So I have something to work to?