I have been toying with the idea of a short list of the airguns one might collect because of their importance in the development of the sport and could be used to illustrate the key points in the development of the modern airgun. Here's my starter, doubtless reflecting my bias toward rifles and especially sporting rifles. I'd be interested to hear what others think.

1. A Gem, for introducing the airgun to a mass market.
2. BSA underlever, for setting the standard for a grown-up air rifle for decades.
3. Sheridan pumper. First US "premium" airgun. Introduced - or popularised - 20 calibre. All subsequent pumpers are attempts to improve on it, often successfully.
4. Original Diana Model 60. First recoilless target rifle.
5. HW80. First gun designed specifically for the "adult airgun" market (FWB Sport close second; Webley Vulcan distant third).
6. Early 1980s Daystate. First modern PCP.
7. Theoben Siroccco. First gas ram.
8. HW77. Just sneaks in because it ruled FT when FT moved from a niche sport to a mainstream one, set a new bar for springers and sired the 97, TX, etc.
9. Theoben Rapid Seven. Brought together the buddy bottle and magazine and made the PCP the hunting tool of choice.
10. No idea. Probably a pistol (Webley Johnstone/Fearn?) or the first SSP match rifle (Anschutz? FWB?) , or something elsse I haven't thought of.

Oddly, aside from an Original 66 (improved 60), the only one I currrently own is the 77 (three of them) and that's the one I'm least sure about.