I have an Illinois serial#3761170 not sure if its RR or not? I know this much its 19 Jewels, Adjusted 3P Double Roller. As far as the size its got me stumped I know the movement measures close to 43mm? I have attached a pic of the movement hope that helps..
Your Illinois is a 16 size, pendant set movement made in 1920. It is a Model 7, Grade 306.
By this time most railroads in the US and Canada required that new watches entering service be adjusted to at least 5 positions and be lever set. For these reasons, these movements are not considered railroad grade, although it is possible that some specific small roads might have allowed them into service.
From what I know the jewel count increased over the years for RR approved. What little I know is the first RR approved had 17 jewels and it went up form there. Also I thought that a 5 position ajust was called for, but I may be wrong.
Also I thought that a watch has to be a size 16 or 18 to fall under RR approved too.
I'am also looking at the complete price guide to watches. it has a Illinois watch Co. Model Chart in it.. on that model its showing DR & Improved RR Model. But also on this chart the Serial#'s dont match up with the model.. So the chart could be off?? not sure??
Railroad watch inspection has been around in the US since the 1850s and probably earlier. Kent Singer has written about these standards and how they evolved over time. You can read the complete history at: http://www.pockethorology.org/Railroad/Railroad.htm
There are two sources for Illinois serial number data. Bill Meggers, in conjunction with Roy Ehrhardt published the definitive work (at the time) "American Pocket Watches - Illinois Watch Co". This should still be available at Heart of America Press, http://www.hoapress.com/bookcat.htm
There is also an Illinois datbase available on a CD. Created by Russ Snyder, it is available through NAWCC Chapter 149, The Early American Watch Club. Contact Jon Hanson for details.
Sometimes, detemining whether or not a watch is railroad grade, or not, can be very difficult. A number of us who have been studying the subject for a long time, such as Ed who just posted on this thread, can tell at a glance. But if we're asked the specific regulation, one way or the other, our answers can be inconsistent.
The problem partially lies in the fact that each railroad had its own time service rules. Even if several roads contracted out to the same time inspection service, there were differences. One example is that in the 'teens, Montgomery dials were prohibited on a number of roads whose programs were administered by the Ball Time Service. Nevertheless, these dials were permitted on the Chicago, Rock Island & Pacific (the Rock Island Line) a Ball Time Service subscriber.
So it is with adjustment to position. In general, during the period 1906-1908, the rules changed to require that watches needed to be adjusted to five positions. However, a number of roads, the Union Pacific perhaps being the best known of the group, permitted both Burlington and Santa Fe Special watches to be used in railroad time service. On the whole, these watches are widely believed to have only been adjusted to three positons.
From this, one might be led to belive that other watches, adjusted to three (or even four) positions would be allowed to enter railroad time service. Yet, there is no clear evidence of this and until such time as railroad time service documents come to light that support this contention, the exception will be believed to apply only to the Burlington and Santa Fe Special watches (at least those whose dials and size met the other requirements).
Other murky factors are Roman dials and hunting-case movements. Information has come to light over the last few years to indicate that these were allowed to enter service (at least on some major railroads) as late as 1910 and perhaps long after that date. The surviving documents contain no clear prohibitions of these two features until much later than 1910.