piece of 4" diameter ABS or PVC piping
piece of 1.5" diameter ABS or PVC piping
coupling sleeve, threaded on the inside at one end
several pieces of foam pad or sponge (silencing
You may have to alter the diameter of the pieces to
match the specifications of your gun. You shouldn't need
to buy any new piping, use the leftovers from your
barrel and combustion chamber.
Don't forget if you have a lesser diameter on any of
these pieces that you ought to increase the length to
First and most importantly, the inside of your coupling
sleeve and the outside of your gun barrel need to be
threaded. This is because you do not want to permanently
affix the silencer to your gun for various reasons.
having the threading done, use your piping glue to
glue the piece of 10" long, 2" diameter
piping into the non-threaded end of the coupling
that has set, slide the 4"->2" reducing
bushing down until it is flush against the coupling
and the 4" end is open opposite the coupling
sleeve. Apply glue, and allow setting.
a drill, drill many (how many is up to you, but not
TOO many) tiny holes into the 10" piece of
piping. Use the smallest drill bit you can find (I
don't have any suggestions), or else you'll end up
turning your potato into French fries when you fire
it. These holes allow the air to expand before
exiting the barrel.
glue the 4" diameter piece of pipe into the
open end of the bushing. You should have a pipe
within a pipe now otherwise you got confused
somewhere. Allow the glue to set, as usual.
the foam or sponge into the area between the two
pipes, the tighter, the better. This silences and
slowly allows the air to expand as it hits it. This
is what will absorb the bang.
All told, you should have a functional silencer. I do
not know the exact length of the coupling and bushing,
so you may need to shorten (or length!) the 2"
diameter. pipe to make them even.