Here is another link to some additional interesting information. Pls note the specific remarks about cylinder and Skeet #1 chokes. Perhaps it will provide a bit more insight on that subject.

http://www.fieldandclays.com/expert_chokes.htm

Of the I.J. Skeeters that I have seen and fired [I only have any real first hand shooting experience with one 28ga. Skeeter] they were made for the game just as their name implied. However, we all know that makers would and could make what the customer wished and something as easy for a mfg to do as supply a standard gun with a dif choke was certainly among the easiest requests to honor. I expect, but do not know for a fact, that many Skeeters were the owner's field guns. The game as originally played was a low gun game with the terms 'pull' & 'mark' being used for the respective targets. I always wondered if the latter term was not a command used for the dog to 'mark' the farther bird [in the field]. In any case, the skeet #1 and skeet #2 chokes were sorta IC and what today is termed 'light mod." by the sporting clays shooters. Of course, the terms are meaningless w/o some pattern testing for the specific loads being utilized.

BTW, the 2.5" .410 paper cartridges were loaded w/thin card wads & only 3/8oz. of shot until the very late 50's or early 60's. If you go back and look in the skeet records you will find there were not but a very small number of 100's broken w/the .410 prior to that time period. I want to say that prior to 1960 it was less than ten, total, in the NSSA record books, but its been a while since I had those interests.