I'm inclined to agree, I did a brief before and after test of my own 28 ga. with a Jack Gardner half-round 30" barrel on a T/C Penn Hunter. I only went to improved cylinder on that one because I viewed it as primarily a bird & bunny type of gun. My test was far from thourough but my subjective impression was that it was less accurate after jugging. I still haven't tried a lot of loads, it may be that another load would do better but the load I tried went from 4" groups to 6" groups at 50 yards after choking to improved cylinder. That didn't depress me at all since I use rifles for ball shooting and the pattern with 6s was just what I wanted.
Doubles are no problem and there is no need to remove ribs or hardware. I work from the muzzle end with a tool I built in what is called "spill boring", a wood backed single point reamer, turned by hand, with shims to adjust the cutting depth. The shape of the recess is determined by the shape of the reamer and, of course, a deeper recess will also be longer.
My thinking on chokes in general is that the cylinder bore is just fine for most upland game hunting where shots are within 25 yards. Improved cylinder is my favorite all around choke, giving a pattern nearly as large as the cylinder bore but more uniform and with a slightly more dense center which will give another 5 yards of effective range. Tighter chokes reach longer range by thickening up the center of the pattern, in effect you get two patterns, the dense center and the outer fringe which is much less dense. For this reason I consider full choke to be a specialized choke, effective past 50 yards with the right load, but only if one shoots well enough to put that dense center on target.
To maybe explain what I mean, when I check patterns I draw two concentric circles. I use the standard 30" diameter circle to get an overall percentage but I then draw a 21" center circle which has half the area of the 30". So if the pattern were uniform overall, there would be the same number of pellets in the center as in the outer ring. That happens with chokes no tighter than improved cylinder. If the overall percentage runs no more than 50%, you may find 25% in the center and 25% in the ring. But with tighter chokes, pellets are pulled from the ring into the center so that a 70% full choke will run more like 50% in the center and 20% in the ring, big difference there, the center having 2 1/2 times as many pellets as the outer ring. Thus, for shots past 30 yards, you really have to center the target with the full choke. That's no problem for aimed shots at stationary or slow moving targets but puts a real premium on just the right lead for flying birds or bouncing bunnies. On the other hand, if you center a bird at 20 yards with a full choke it will be mangled.
Full choke makes a fine turkey and trap gun but is just a bit too specialized for most flying game. That is why modern shotguns use interchangeable choke tubes, because no one choke does it all. :grin:
