Q: I am currently a C Class Shooter and I see a lot of shooters around me changing cokes and shot sizes. What do you prefer and why?
A: I personally shoot fixed chokes (Mod and Mod) in my Peruzzi, which may give you some insight as to my bias. I shoot 7½ shot and, when competing, I carry 8.5or 9 shot for closer targets or those that show belly or face like a battue. Chokes are a personal choice as is the decision to change to affect pattern size.
With that said, there is plenty of technical evidence that changing chokes and/or shot size will change pattern density at a given distance. For the sake of available space as well as the plethora of good information available, I will defer to others regarding the technical justification for choke changing.
The advantage one gains from changing an Improved Cylinder choke to a Light Modified for example (5/1000th”), or changing shells from 7½ to 8 shot, is infinitesimal. I am not suggesting that you should convert to fixed choke or avoid changing chokes or shot size altogether. However, the advantage of changing chokes to affect a very small change in pattern density is, in my opinion, counter productive.
I can share one ironclad observation as it relates to shooters and changing chokes. With few exceptions, a shooter will place less importance on changing chokes as he or she progresses and improves in shooting proficiency. The more mature shooter understands that the time spent fiddling with chokes can be better spent studying the targets and tweaking the shot plan.
My suggestion is that you select a good medium constriction choke (IC or LM) and change chokes only when you are presented with an “extreme” target such as a crossing rabbit at 15 yards or a flat, edgy crossing standard target at 50 yards. I urge my students to spend more time on shot planning and executing a rock-solid pre-shot planning process than fiddling with chokes.