Terry G said:
One gent was claiming steel shot has a greater range out of an modified choke than a full choke because the shot is not as constricted.
In practice, steel shot shoots about one choke tighter than lead. In other words, an improved cylinder pattern with steel shot will approximate lead shot from a medium choke. This is due to the lead being deformed, whereas steel is not.
If shot pellets are deformed, they will randomly spread out, thinning the pattern. However, with steel the shot can be too constricted, causing a "billiard ball" effect, wherein the shot bunches up as it passes through the choke. This may result in wide, thin patterns.
Since choke is a vague term at best, I recommend that you pattern the desired shot. You may find that full is indeed too tight and gives blown patterns.
The range thing has to do with the formation of a subsonic bow wave abound most of the pellets in flight. This bow wave thing is why geese fly in a "V". Pellets which wander outside of the wave slow more readily and soon become useless.
Remember: Even, consistent patterns give the maximum effective range.