I believe that the Long Range option is NEARLY ALWAYS recorded. Obviously, it was missed a few times. I am really surprised that it was missed on your Trap Grade. I have observed that the information in the ledgers appears to be more accurate on grades above the Field Grade(which made up +80% of the total production). Of course, I can only include information in the research letters that appears in the ledgers.
The Long Range/Wild Fowl option is one of the most misunderstood features. Since we have a Long Range/Wild Fowl box that can be checked on the letter application form, many people (probably 1 in 5) check the box if they have a 12 gauge shotgun made in any period, especially if it has 32-inch barrels. I've received a few forms for 20 and 16 gauge shotguns with feather-weight frames with that box checked.
The LR/WF guns usually had 3-inch chambers, a reinforced barrel loop, and were stamped LONG RANGE or WILD FOWL on the barrel lug. The frame nearly always was a regular-weight, and was the same size as a standard regular-weight. No one has definitively shown that the chokes were different. Primarily, it appears to have been a Hunter Arms Company marketing ploy designed to use the option of shooting 3-inch shells to sell more shotguns.
I have found that automatic ejectors vs. shell extractors is the only option more misunderstood by the casual owner/collector of L.C. Smith shotguns.