A44, I completely understand your yearning for a way to date guns from a Maker with non-extant records, I tried for years to do the same for Blanch but I fear you are entering a mine field of conflicting purposes for different Patentees and all sorts of financial shenanigans between the Big Names.
You will see far more patent stamps on guns by Scott and Westley Richards than any other maker as they were major inventors (or purchasers of patents) who sold huge numbers of guns to the trade to be retailed under the 3rd party's name. In fact Scott sold almost nothing under their own name in Britain, preferring to have a domestic business model that supplied guns to the trade. In contrast they sold a majority of guns for export under the Scott name.
As regards the use numbers and patent stamps applied by Scott, I think they were used as a way of checking that guns in circulation had used a patented mechanism with their permission (whether or not a royalty had been paid) and were nearly always applied by the Patentee, not the retailer. The most obvious exception to this is the Scott Spindle, the stamp for which you rarely see on anything but the earliest examples although it was used extensively and royalties charged. I think the exception reflects the deal done by Purdey with Scott whereby Scott got to charge royalties on the Purdey Bolt and their spindle for provincial makers (and export?) while Purdey got to charge royalties for the Scott Spindle and their bolt for London Makers.
Furthermore, the common practice of issuing blocks of serial numbers to trade makers for guns to then be retailed by the 'Maker' could very well have been used in reverse, issuing blocks of Use Numbers to a Maker for their exclusive use. In fact I have seen Gas Check Use Numbers with a letter prefix of 'H' on some H&H guns. In fact I think it equally likely that Scott supplied batches of ready stamped actions (receivers to you) to Makers which may have been used to produce that model of gun over a period of years, if not decades. An example is the 1st type H&H Royal which always (famous last words!) has the Gas Check but was actioned, stocked and screwed in many cases by John Robertson of later Boss fame in his independent Soho workshops. These almost identical guns were made from the late 1880's to mid 1890's in substantial numbers.
