No way to answer without the sn.
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This is a Blackpowder firearm, & there is no Ammo currently manufactured for it.
I think you are asking about a forehand wadsworth British Bulldog not a BB gun. As far as I know, I do not know of any Forehand Wadsworth BB guns. Please rephrase your question and re-post it.
Forehand & Wadsworth
U.S. Patent Office
"caliper" is not a term associated with handguns. There is no way to answer the question with just the serial number.
Forehand Arms was the successor company to Forehand & Wadsworth. They were in operation from 1890 to 1902. Not aware of any serial number database for them. Sorry.
50-500 USD depending on specifics
Forehand and Wadsworth (Forehand Arms) was in business from 1871 to 1902. Unfortunately, there are no serial number records for this company that has been closed for 116 years.
50-300 or so
Forehand and Wadsworth was established in 1871 and in 1890 the name was changed to Forehand Arms Company. In 1902 Forehand was taken over by Hopkins & Allen who continued to manufacture many of the same models, changing only the markings. Hopkins & Allen went out of business in 1916. It is not likely that the exact date of your firearm can be established- sorry.
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