Thanks for these two Links. These are two more excellant examples. On the second Link, with a 1711 date on the lock plate, which I'm sure is correct. Notice by this date the lock is now a bit more simplified and doing away with the bridle between the frizzen and frizzen spring. Also note the butt stock is now a bit more streamlined and less cumbursome. Advancement was slow during this period, but did continue.
The first Link, with the Dunster Castle gun, they give a date of about the early 1660's. This also seems correct. Note how similar the butt stock and other features are to your gun. Here, the lock has earlier features than the 1711 gun. The lock retaining it's wide, matchlock type pan, frizzen bridle, etc.
Which brings us to your gun. As mentioned, the stock design on your gun is very similar to the Dunster Castle gun. But the lock on your's: The external hammer stop is a carry-over from the earlier snaphaunce/English locks. Also the frizzen on your gun: While very robust looking, it appears the striking face portion is more narrow than the pan cover portion. Seems like a curious, early feature from the locksmith who built it.
So with the current evidence, one could reasonably speculate that your gun - or at least the lock - pre-dates the Dunster Castle gun a bit. If someone with more knowledge, told me that your gun would date to the late 1640's to 1650's period, I could reasonably agree with them. In any case, it certainly pre-dates 1670. It would be great if someone who is an expert with these early English doglock muskets could view this gun, along with some detailed photos, and offer their assesment.
Meantime, looking forward to any lock photos you can offer.
It's a wonderful aquisition Mark. The earliest example of a doglock I have seen.