Surujin (スルジン, Weighted Chain)

The surujin (スルジン, also written 石投 or 鎖) is a flexible weapon consisting of a rope, cord or chain with weighted ends. It is the only weapon in the Taira curriculum that extends the practitioner's effective range beyond arm's reach through projectile-like throwing and entangling techniques.

Physical Characteristics

Property	Detail
Length	2–3 m (200–300 cm) total
Weights	Stones, metal weights, or shaped metal ends
Material	Rope (traditional) or chain (modern)
Variants	Tan surujin (short) and naga surujin (long)

Technique

The surujin is used in several ways:

• Swinging and throwing: the weighted end is swung to build momentum and cast at a target's limbs or weapon
• Entangling: wrapping around an opponent's arm, leg, or neck
• Striking: using the swinging weight as a flail-type impact weapon
• Controlling: a caught limb is pulled off-balance while the other end is ready to strike

The weapon demands significant practice to control because the dynamics of a spinning weighted chain on the end of a rope are unpredictable for beginners.

Kata in the Taira Curriculum

• Surujin no Ichi (スルジンの一): The first surujin kata. Introduces the fundamental throwing, entangling and striking patterns.
• Surujin no Ni (スルジンの二): The second kata with more complex application sequences.

Historical Context

The surujin is likely related to the throwing-stone traditions documented in Okinawan and Chinese military records. The Tsuken sand-throwing techniques preserved in Tsuken Sunakake no Kon (usually classified as an eku kata) show the same conceptual logic: range extension and distraction through thrown or swung objects.

Sources

1. Surujin — Wikipedia: Physical dimensions (2–3 m rope with weighted ends), usage techniques (throwing, entangling with hōjōjutsu-style wrapping, spike for coup de grâce), classified as chain weapon
2. Okinawan kobudō — Wikipedia: Confirms two surujin kata in the Taira curriculum
3. Matayoshi Kobudo — Wikipedia: Matayoshi suruchin kata listed as Suruchin no Kata