That's indeed the point, thinreadline:
finding out what sources the 'experts' or prop masters relied on ...
I am afraid I am unable to tell what that special pistol was supposed to be as I did not see it.
From rather sad experiences of my own, though, I can tell these film guys usually just resort to information readily available, e.g. some standard encyclopledia or of course the internet.
These sources are normally taken as granted, regardless of their authenticity.
The next thing is: the realization must be cheap and readily accessible.
Atfer all, how often have we watched tv series or movies with 19th c. Colt revolvers being fired endlessly without reloading? With flintlocks being fired without the frizzen even shut? Firing guns without the tiniest trace of a recoil?
The story of misleading the masses when it comes down to weapons is way too sad to be carried on.
Their motto seems to be: who cares anyway? A bunch of weapon freaks who will actually know? Suckers ... you sure can mess around with these!
To be honest I do remember watching one British tv film on Sir Francis Drake, as a boy in the 1960's, probably this:
http://en.wikipedia.org/wiki/Sir_Fra...28TV_series%29
- and I do remember a very good representation of a late-16th c. wheellock dag in there!
Best,
Michael