Multum in Parvo by Jack Sharkey (The Gent, December 1959)1 isn’t actually a short story but a quartet of vignettes that each end in a pun (or two, or have them all the way through)—Feghoots, as I believe they are called in the SF field.2
The first, Robots, is a fairly straightforward piece involving the construction of a card-playing robot in 1653, which builds to a decent single pun ending; the second, Aircraft, has Icarus flying towards the sun with a double pun ending, both of which are both okay; the third, Vampirism, really goes for it, and has eight puns (maybe more) on the way through—this is the best of the four by country mile; the last one, Atomic Fission, has a decent single pun ending and a coda about fallout that I didn’t get (the Vampirism one would have made for a stronger finish).
I’m not big on puns but this was okay, with the third section having considerably more bite than the others. Boom, tish.
1. In The Great SF Stories 21 (1959), edited by Isaac Asimov & Martin H. Greenberg (which includes this story), the editors report on two further ‘Pavro’ stories in Gent magazine (which are not listed on ISFDB): Son of Multum in Parvo and Son of Multum in Parvo Rides Again.
2. The Wikipedia article on Feghoots.