Artillery Test on Harzhorn Battlefield (235 AD)

[P. Clodius Secundus]

Most interesting (part of)statement is that they estimate to reach an effective range of 300-400 m
when this piece is fully "tricked out".

If they keep building it backwards I think 300-400m is a bit ambitious, but possible. That would be a respectable range for a wood-framed Vitruvian era scorpion, but it is only about half of what the later iron-framed ballista they a trying to build should do.