When was my FWB65 made?

When I bought my Model 65, I immediately emailed Feinwerkbau to find out when it was made. They replied that while they do have the records, they charge 60 euros to check. Understandable, I suppose; they are in the business of making hi-tech match guns, not running round the basement looking for serial numbers for something they made 40 years ago just to satisfy a collector.

It is however possible to get an approximate date for your Model 65. A thread on TargetTalk lists the following serial numbers/production dates:

#5,324 was made in October 1967
#7,453 was made in June 1968
#72,294 was made in June 1975
#107,945 was made in September 1980
#132,326 was made in October 1985
#141,456 was made in February 1989

The Model 65 was produced between 1965 and 1998, and around 145,000 pistols were made.
The Model 80 was produced between 1977 and 1986, and around 48,000 were made. The Model 80 is easily recognisable by its squarer trigger guard.
The Model 90 was produced between 1982 and 1992, and around 20,000 were made. The Model 90 featured an electronic trigger mechanism.

Pistols made before 1973 do not bear the "Freie Waffen" mark, a letter F in a pentagon.
Pistols made before about 1977-80 had a short spur at the rear of the frame; those made after had a longer spur. Later pistols also had a wider rear sight element.

There's a great discussion of the variations of the Model 65, including the US market short barrelled version, on American Vintage Airguns, here.