Proposed Stats:
missile speed: 38 - roughly the same as a mid-tier bow
weight: 5 - relatively heavy
accuracy: 75 - least accurate crossbow
difficulty: 9 - middle tier requirement
speed rating: 105 - comparable to heavy crossbow
max ammo: 5 - 5 shots in the chamber
thrust damage: 30 pierce - lowest damage crossbow
slots: 2
Cost: 7481 - between light and regular crossbow
Upkeep: 524
Can't Reload on Horseback
1.5 second delay between shots
I've seen this thing fired on Deadliest Warrior. I also have some stats here that I think show your proposed stats to be quite generous.
Stephen: Your account on the Chu Ko Nu looks pretty much on to me, except that the iron lever that draws back the machine gives you about a 3 or 4 to one mechanical advantage, so the actual draw on the prod can be as much as 100 lb (at about 6-7 inches), with the draw on the lever still being only about 25 lb. This still makes a pretty weak bow, with about as much power as perhaps a 35 or 40 lb. handbow. (Compared to English Longbows from ship Mary Rose, that are calculated as a minimum of 100 lb. draw at about 22 inches, and the average bow from that find of 139 bows coming out at about 125-130 lb. draw. (The heaviest max out at about 175 lb. of draw. That oughta take a pretty beefy fellow to draw.....! )
The darts were quite small (8 inches.)
At best that is going to be short bow-bow range of 18-20 damage. The darts are so small they won't be adding any damage, even if pierce. In addition, from the Ming Dynasty text
It fires weakly so you have to tip the darts with poison
In other words, they weren't built to kill on their own power.
First, the maximum practical rate of fire is about 1 shot a second. Attempting to go faster than that can lead to misfires and scattering bolts all over creation. Sometimes the thing misfires, and 3 or 4 of the top bolts in the magazine hop right out of the magazine if it is not closed. /With a little practice you can keep the 10 or so bolts of a magazine pretty much in a 3 foot circle at 15-20 yards.
So a 3 foot circle at about 5-7 steps away from your target. That is not very accurate and at a short range at that. Tests would have to be done, but you are looking at more like a 35-50 accuracy, not 75.
Not just that, but given the likely hood of bolts scattering everywhere, these are not simply not able to reload from horseback, but not usable
at all.
The bolts for this machine are generally unfletched
In other words, past 15-20 yards they get even more inaccurate and I've seen them tumble in air, meaning no penetration at all.
The Chu Ko Nu is bulky and unwieldy, though not particularly heavy. It may weigh 10 lb. with bolts in magazine.
Your 5lb weight is too low.
The main thing these had going for them was:
1: they are cheap to make
2: it doesnt take much training
3: put in the hands of hundreds of peasants, it could rain down thousands of projectiles in minutes from high walls at unarmored horses. Accuracy didn't matter, just volume did.
In other words, from a height you could fill the battlefield with projectiles. From the ground, you could fill the next 100 yards or so.
So I ask you, is this what cRPG needs? A weapon designed to spam hundreds more projectiles into the battlefield in a short time span? You think a hill with 10 archers and xbowmen is a pain now with their limited fire rate? Just wait until they are putting out 100 projectiles in 10 seconds, even if they are inaccurate.