Hi David,
In Germany and Switzerland they were called
Fuss-Streithammer (war hammer for foot soldiers).
I attach two late 15th c. samples from the collections of the German Historic Museum Berlin (b/w) and another fine late 15th c. item retaining its warding off disc (
Brechscheibe) - I could not find the correct English term. Anyone ready to add it?
Unfortunately their weights are unrecorded.
The hafts are either of oak or ash.
Best,
Michael