Technical information

Practical A.E.G Upgrade 2006
Page 122 Copyright 2005,06 The AirsoftPRESS (Hong Kong). All rights reserved.
Can the one-piece type hopup increase accuracy? Does it worth the $?
According to the Bernoulli's principle, if a bullet is given a backspin an
overpressure is formed under the bullet and an underpressure is formed on the
top of the bullet. The bullet is therefore sucked up - this is why it can fly farther.
In theory, the hopup back spinning mechanism adds instability to the bullet
flight path as different bullet surfaces may react differently with different hopup
rubbers, thus making the back spinning behavior highly unpredictable. A poor
quality hopup unit with a shaky bucking mechanism can also produce problems.
Based on our experience, a high quality one-piece metal hopup unit does seem
to reduce such uncertainty and increase accuracy significantly when being used
with a high precision inner barrel. Accuracy is greatly improved when this combo
is loaded with the heavier 0.25g BBs.
A one-piece metal hopup unit for M4: