As the late shotgun guru Bob Brister wrote: "Full choke is a demanding mistress; improved cylinder a forgiving friend. IM is WAY too tight for preserve pheasants. I've told this story before:
I'm far from being an excellent shot. However, when I had a writing assignment where I knew that I'd have a lot of chances on good preserve roosters (birds that didn't need to be booted out of the cover), I decided to try an experiment. At the time, I had a Parker Reproduction 28ga on which I'd had the tight chokes opened to IC/M. I reloaded the standard 28ga load (3/4 oz of shot) with #7's. After flat missing the first bird I shot at, I then bagged 27 in a row. A couple of them required a 2nd barrel. And good dog work by either mine or the preserve's recovered a couple that came down but hit the ground running.
On pheasants, especially if you're shooting a 16 or a 12, 1 1/8 oz 6's is more than enough. And IC is more than enough choke unless you have unusually nervous birds. Save the IM for late season wild roosters.
