I was always too lazy to do extensive pattern testing. As a life member of the NRA for 40 years & a member still longer, back when the Rifleman was still a shooters magazine, upon testing a shotgun they always showed pattern tests. They showed typical 40yd test with 30" % as well as % in an inner 20" circle. A typical pattern will show greater density in that inner circle, surrounded by a less dense circle, further surrounded by scattered & eratic fliers. A factor that became obvious to me over the years was how often the difference between say a 70% & a 50% pattern was entirely within that inner circle with the number of shot within the outer ring being virtually identical. Obviously the "Extra" shot in the inner portion had to be brought in from outside the normal 30"s. Anything hit outside this normal pattern will be problematic as to a clean kill with the more open chokes having only a very slight advantage in this regard. Open chokes are simply not a substitute for proper pointing. What thet do offer is a more uniform spread over their entire patern with less "Mince Meat" on a centered hit at normal ranges. A choke of .010"-.015" constriction is entirely adequate with appropriate loads to reach to 40yds. To go much beyond requires that concentrated center, but then one must consider if they have the ability to "Always" center the shot as that center will of necessity be surrounded by a ring of considerable size almost guaranteed to only cripple. "I Don't" so the two guns I have used with good success over a number of yrs are one having .010"-.012" in both bbls & another with .012"-.024". I do have a nice H grade Lefever which is tighter (Full) in both bbls, but I have not yet decided to modify them & probably won't, just adjust the loads.