Originally Posted by Straybow
Hand-spanning a ~125 lb crossbow gives, at best, about 8 shots/min. Using belt hooks or a lever for heavier crossbows is significantly slower. A cranequin or winch for really powerful crossbows (400-800 lb or more) has to be attached, cranked, and detached and stowed, which could take a minute or two.
Minute or more would be mostly very lazy rate, vast majority of bows probably didn't require that much time, with enough effort.
Unless sad remains of my German are failing me, this cranequin allows to draw about 1100 pounds over 140mm, in 25 seconds during which hands will cover about 20m, providing mechanical advantage.
So with a lot of effort and dextrous use one shot every 30 seconds would be good guess.
Crossbows of about 400 pounds generally weren't of winch etc. variety, save for hunting ones, where rate of fire didn't matter much anyway.
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