two main forces at work inside the Barrel
of the gun.
The first force is from the
expanding gases which create the movement of the paintball.
The second force is the friction
between the ball and the barrel. Many manufacturers
aim to produce a maximum velocity
of 300 fps at the muzzle. Many laws and regulations are
based on the 300 fps velocity.
Paintball markers have various
stages of gas regulation, professionals have multiple stages
to ensure constant pressure and
velocity. For my example I'll base off a single stage marker
that is more common for regular
Using 300 fps, 12 inch
and no friction in the barrel we can find the average pressure as the
ball moves through the barrel.
m=3.2g (Gary Dyrkacz and Neal
Dyrkac) 1 g=6.85217x10^-5 slug
inside the barrel can be found similar to the friction of the
bolt/slide from the previous page.
F=Friction Force, μ=coefficient
Just like before to maximize the performance we need to
decrease the coefficient of friction this can also be done with a
Normally if you hold the barrel of your marker vertical without adding
lubricant a paintball won't fall though the barrel.
After adding lubricant most barrels will pass a paintball which then
reverses the equation.
Assuming a lubricated barrel where μ(N)=mg we can solve for how
much velocity is lost from barrel friction.
Here we see that barrel friction
causes a very small percent of velocity to be lost.