Unique weapon of the Ming Dynasty — Zhu Ge Nu (諸葛弩)

Repeating crossbow is one of the unique inventions of China. Although the invention is commonly attributed to Zhu Ge Liang (诸葛亮), the basic design actually predates him by several centuries.

Liang Shi Bing She Lian Fa Nu (兩矢并射連發弩, lit. 'Double-shot rapid fire crossbow')

Earliest surviving example of a repeating crossbow, excavated from a Chu tomb. Currently kept at Jingzhou Museum.

Excavated from Tomb 47 of the Qin Jia Zui (秦家咀) tomb complex, this is the earliest archaeological evidence of a repeating crossbow, dated to 4th century BC. Note that this crossbow predates all written records of repeating crossbow, so it does not have any official or historical name. It is commonly referred to as Zhan Guo Lian Fa Nu (戰國連發弩, lit. 'Warring States period rapid fire crossbow') or Chu Guo Lian Fa Nu (楚國連發弩, lit. 'Rapid fire crossbow from the State of Chu').

Internal workings of the Lian Fa Nu. Early restoration attempts created a model that does not have crossbow prod, but this was fixed in later models. Image taken from 《戰略‧戰術‧兵器事典》 vol. 1.

Replica Lian Fa Nu alongside the original fragment, Military Museum of the Chinese People's Revolution (exhibition).

Lian Fa Nu is actually more advanced than repeating crossbows of later period. Its box magazine, large enough to hold twenty bolts (for ten shots, as it shoots two bolts at once), is fixed on the stock and therefore more stable. Its vertical foregrip and spanning device also allow the user to shoot the crossbow with a slingshot stance, making it easier to aim. Nevertheless, Lian Fa Nu does have several drawbacks, as it requires a complex metal trigger mechanism (making it too expensive for civilian home defence), is prone to jamming, and is weak even by repeating crossbow standard.

Ming Dynasty Zhu Ge Nu (诸葛弩, lit. 'Crossbow of Zhu Ge Liang') or Lian Fa Nu (連發弩, lit. 'Rapid fire crossbow')

Drawing of a Zhu Ge Nu, from 'Wu Bei Zhi (《武備志》)'.

Sometimes romanised as Chu-Ko-Nu, this well-known repeating crossbow only dates back to Ming Dynasty. It is a rugged design that is cheaper (as it does not require any metal parts) and more reliable than ancient Lian Fa Nu, and serves as the base model for later derivations.

Zhu Ge Nu has a magazine that holds ten arrows, and is spanned by a lever. The lever works on a similar principle to that of a European latchet crossbow, in theory allowing a very powerful prod to be used. However Ming Dynasty Zhu Ge Nu only mounts a small prod made of Chinese mulberry or lashed bamboo strips. Unlike later models, Ming Dynasty Zhu Ge Nu shoots fletched arrows.

Components of Zhu Ge Nu, from 'Wu Bei Zhi (《武備志》)'.

The design of Zhu Ge Nu reflects a mindset that favours rugged reliability over pure performance (which may be the reason why powerful but delicate composite recurve prod was not used), a mindset shared by many militaries in the world. Nevertheless, Zhu Ge Nu was still considered ineffective as battlefield weapon.


Qing Dynasty Repeating Crossbow

Training manual for repeating crossbow, from 'Bing Ji Zhi Zhang Tu Shuo (《兵技指掌圖說》)'.

Save for some minor differences, Qing Dynasty repeating crossbow follows the exact same design as Ming Dynasty Zhu Ge Nu. Most Qing Dynasty repeating crossbows have single piece bamboo or wooden prod, or prod made of several flat strips of bamboo lashed together. Many Qing repeating crossbow shoots fletchless bolts, sometimes jokingly referred to as “chopsticks” by contemporary Chinese people, although exceptions do exist.

Note that the term "Zhu Ge Nu" was rarely used during the Qing period. Repeating crossbow was known as Nu Gong (弩弓, crossbow), as it was the only type of crossbow that saw regular (albeit still extremely uncommon) military service in the Qing army.

An eighteenth century Qing Dynasty double-shot repeating crossbow.

An eighteenth century Qing Dynasty Lian Zhu Nu. It can still shoot normal bolts.

Several variants of repeating crossbow, including a double-shot variant and a stone bow variant known as Dan Nu (彈弩, bullet crossbow) or Lian Zhu Nu (連珠弩, lit. 'Rapid bead crossbow'), were developed during Qing period


Korean Repeating Crossbow

Drawing of a Sunogi, from nineteenth century 'Hungug Sinjo Gigye Doseol (《훈국신조기계도설》 or 《訓局新造器械圖說》)'.

Korean version of repeating crossbow can be called a Suno (수노 or 手弩, hand crossbow), Sunogung (수노기 or 手弩弓, hand crossbow) or Sunogi (수노기 or 手弩機, lit. 'Hand crossbow machine') and follows the same basic design as Chinese Zhu Ge Nu. Nevertheless, Sunogi has several modifications that set it apart from, and arguably make it superior to, the Chinese version.

Replica Sunogi in cocked position. Note the upward-tilted prod.

One immediately noticeable feature of the Sunogi is that it has longer tiller (stock) than Chinese Zhu Ge Nu, and its lever and magazine are mounted closer to the butt. This allows for longer powerstroke and higher velocity arrows. To compensate for longer distance between the string and the notch of the spanning lever, Sunogi's prod is mounted in such a way that its limbs will pivot upward when the lever is cocked. The overall larger size of Korean repeating crossbow also allows a more powerful composite recurve prod (basically a modified Korean bow) to be used. Like Ming Dynasty Zhu Ge Nu, Korean repeating crossbow shoots fletched arrows.

Replica Tanno, Young Jib Bows & Arrows Museum.

Replica Samsisunogi, Young Jib Bows & Arrows Museum.

Koreans had their own variant designs of Sunogi, including Tanno (탄노 or 彈弩), the stone bow version of Sunogi, as well as Samsisunogi (삼시수노기 or 三矢手弩機), a triple-shot repeating crossbow.