AIRSOFT - The two main lengths of Hi-Capa pistols are 5.1 and 4.3 inch (outer barrel measure). Their inner barrels are usually 113 and 95mm, respectively. In small airsoft arms, longer is usually better. It is possible to install a precision barrel intended for the longer 5.1 Hi-Capa to the shorter 4.3 Hi-Capa. The inner barrel tip can be hidden under a thread adapter and doesn't bother if you are to use a tracer anyway.
The Vorsk 4.3 Hi-Capa has a 95mm inner barrel, with a 6.03mm inner diameter. Here, I installed the Maple Leaf 113mm precision barrel, which as an inner diameter of 6.01 (so it is very tight).
With the stock Vorsk barrel, the mean muzzle velocity was 89.7 m/s (294.4 fps), with a standard deviation of 0.97 m/s (3.18 fps). With the Maple Leaf barrel, the muzzle velocity was nearly 9% higher: 97.4 m/s (319,7 fps), with the smaller SD of 0.58 m/s (1.9 fps) indicating more consistent shots - less variation in muzzle velocity.
A precision barrel is an important upgrade part to increase the gun's power, as it won't put the gun under more stress.
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