I have had a request for the brief collation of data I have put together, so herewith a screenshot of an Excel worksheet of 18-Pr head stamp dates and Lot codes from the Canadian Cartridge Co. I have gleaned the data from photos and descriptions posted on BOCN and elsewhere.
Canadian Lot size was 400, give or take a few for various reasons of proof or surplus. The Lots were identified by incremental letter codes, starting with single letters A to Z around mid 1915, then incrementing through two letters AA to ZZ, and ultimately to three, AAA to whatever was reached by the end of hostilities.
A couple of Lots are seen to be out of order, perhaps because the Lots failed at some point of inspection and were sent back for reworking, but otherwise the incremental Lot coding with date is very evident when tabulated as shown.
If anyone wants a copy of the Excel worksheet so as to add their own details for their records, PM an email address and I will be happy to send the sheet.
On the screenshot, items in blue are from Ron's posting in this thread.
Any errors in transcription of dates and codes are mine.
Tom.