Perhaps the last thing that might strike you (6)
I believe the answer is:
bullet
'strike you' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for bullet that I've seen before include "Revolver missile" , "Have attraction" , "Small missile from gun" , "Projectile ammunition" , "High-speed projectile" .)