Thank you Chris,
You can often see flared muzzles out there.
HERE is one.
We can also see one in the Museum of Tabor, South Bohemia, dated 1419-1434, used in the city during the Husites wars. Attached is a replica of such example. Amazingly that the Checks called these hand cannons
PÍŠT'ALA, meaning tube, which gave the contemporary name
pistol (actually
pistola in portuguese).
.