What’s the distance on those things?
Depends on the mass of the projectile, and how the throwing arm is tuned.
If its release is tuned for distance and they’re flinging period-accurate projectiles, tuned firmly distance a typical period tree could throw stones about 300 meters.
Depending on the kind of fortifications they were against (and if they had siege engines of their own, or other artillery- bow and arrows, whatever) they might set up a little closer and tune instead for more forward velocity rather than range.
The typical mass was about 200-300 kilograms, or a small sedan. You could go heavier, but that typically reduced range.
200-300 kilograms, or a small sedan
A small sedan weighs about four times as much as that
Get out of here with your facts.
(for what it’s worth, a reliant robin was about 450 kilo curb weight. I’m sure we can find a car that weighs in the range.)
“They would have been pulled up to a castle, maybe 200-300m away and they could have launched rocks, boulders and flaming boulders into castles,”…
https://www.bbc.co.uk/news/uk-england-coventry-warwickshire-65099834.amp