Back to the Basics Series: Disassembling your nelson based paintball gun for
maintenance and cleaning.
March 20, 2002
Back to the basics Series:
Disassembling your nelson based paintball gun for
maintenance and cleaning.
From time to time , every marker needs a good
cleaning. Eventually , even the best of paintball
guns need to be taken apart for a complete cleaning,
or parts need to be replaced. An if you break some
paintballs in your gun at the field, its a good idea
to know how to field strip it , so you can clean out
the mess and get back in the game, not have to leave
Fortunately, most nelson based paintball guns are
very easy to work on, it might be a bit intimidating
at first, but once you understand how the various
parts go together, you’ll be pro at it in no
Before you start, you’ll need a few
Many pump paintball guns require no tools at all to
disassemble, but take a look at yours. You may need
a screw driver, an appropriate sized Allen key, or
even a box wrench or adjustable one. So gather the
right tools for your gun.
Warm water, paper towels, maybe some dish washing
liquid soap if your marker is really dirty. A
squeegee or battle swab .. "oooo" grade steel wool
can be helpful to polish the internals and barrel
Oil is a good thing, and I recommend using oil
specifically designed for paintball guns. Check
with the manufacture for their recommendations
first. Using the wrong oil can cause o-rings
to degrade or swell, eat up your cup seal, cause
your gun to lock up and all sorts of nasty
things. Generally you’ll be okay using
something like KC TroubleFree ™ or GoldCup
™ paintball marker oil. Never , Ever use
wd-40 ™ or lithium based grease or oil, they
can and will destroy the o-rings or create friction
and lock up your marker, especially in cold
Now that you’ve got your supplies together,
spread out a towel, and take a good look at your
marker. Note how the pieces all go together, where
the screws go, how its configured. . If you
don’t think you can remember how it all goes
together, take a picture or use masking tape to
number each part to use for reference later on.
Before you start, make sure the air source or co2
tank is completely disconnected from the paintball
gun. Some guns will actually hold co2 or air in
the valve, and still shoot even with the air source
disconnected, so dry fire the gun a few times if
possible in a safe direction to make sure its
Disassembling a nelson based paintball gun:
Cleaning the components of a nelson based
If your paintball gun has a removable barrel,
remove it. Most barrels unscrew, or have a set
screw on the side or underneath. Set it aside. Many
older nelson pump do not have removable barrels, if
this the case, don’t sweat it, you can still
clean the barrel well, read on. Remove the trigger
frame from the body of the gun. Most pumps like the
trracer have two screws , one under the body in
front of the trigger, and one behind it. Some pumps
may have the rear screw on the top of the gun body.
Remove these and the trigger frame should drop away
for the body of the marker. If you have a bottom
line setup where the bottle screws in at the bottom
of the trigger frame, you can unscrew it from the
upper Air system adapter (ASA) once the trigger
assembly is free from the body of the marker. Set
the trigger assembly aside on your towel. Hint-
its a good idea to line up the parts you remove
exactly how they would be assembled on the gun, so
it’ll be easier to reassemble them later
Pull the ASA straight back, and out of the body of
the gun. Some nelson based pumps have two
additional screws in the body of the gun that hold
the ASA in, remove these before trying to separate
the ASA from the body of the gun. Set the ASA
Unscrew the pump rail screws (if you have them,
some guns are under cocking, the rod should have
come out when you removed the trigger frame.) And
remove the pump.
Tilt the body back, and the hammer, main spring and
bolt should drop out of the rear of the gun, they
might need a little push. Take a good look at how
these parts go together, and remember, so
it’ll be easier to reinstall them later.
Cleaning and polishing inside the barrel/
gun body (if its all one piece, this
applies to both):
Cleaning the internals:
Run a non abrasive cloth or battle swab
though the length of the barrel to get out any
loose or heavy gunk that builds up in there.
Run some warm water through it, to dissolve any
build up of old paint or debris. Caution: the
barrel will conduct heat, using hot water can cause
burns even if you don’t touch the water. The
heat will travel through the barrel and heat it
Swab it to dry, or push a paper towel through it
with a wooden dowel (metal will scratch) , and use
your squeegee to take out any excess water.
Inspect it by holding it up to a light (never
ever do this with an assembled marker, or you risk
blowing your eye out), if it looks shinny
and clean, your done , put it back on your towel.
If not, repeat the about again.
If you have a lot of scratches, or just cant seem
to get it clean enough, find some "0000" steel wool
(about $3 @ home depot) and a wooden, or tape
wrapped rod. Tear off enough steel wool to fit in
the barrel snugly, and use that rod to push it back
and fourth inside the barrel until the grit is
worked out, or the scratches have been polished
out. It may take awhile. Then clean again as above.
Make sure you do a good job, the steel wool will
leave residue behind. Caution: Never use any
steel wool above 00 grade, or you will make it
worse and scratch your barrel up.
Cleaning the rest of the gun:
Wipe them off with a paper towel or rag, if you
have a heavy buildup of grime, you can run them
under warm water, or even soak them in a pan with
dish washing liquid for a bit. Dry thououghly. If
this still doesn’t do it, you can hand buff
the metal parts with 0000 steel wool until there
clean and shiny. Don’t forget to rinse them
again and get out the steel wool debris.
Caution: DO NOT BUFF RUBBER OR PLASTIC PARTS
WITH STEEL WOOL, IT WILL SCRATCH THEM AND POSSIBLY
DAMAGE THEM PERMANENTLY. Use soap and warm
water only on these parts.
Wipe the remaining parts down with a paper towel or
rag, if this isn’t enough you can run them
under warm water and use dish detergent. Make sure
you dry all parts completely.
Now that you’ve got a pile of clean parts on
your towel, its time to get out the paintball gun
oil. Use it sparingly. A little oil goes a long way.
Put a drop on the hammer, and spread it around with
your finger, do the same for the metal part of the
bolt, around all o-rings, the valve tube, and place
where two parts will come in contact with each other.
Its also a good idea to put a drop in the ASA, on the
barrel threads if applicable, on the trigger pins,
etc. After you oil put the parts on a paper towel so
they don’t pick up lint while waiting to be put
back on the marker.
You remembered how the marker came apart right? Good,
because now its time to put it all back together, get
started :) ..
Once you’ve reassembled your paintball gun, its
a good idea to test the action , pump the pump,
BEFORE putting a co2 source on the gun, to
work the oil in and make sure you’ve
reassembled it correctly. You should never have parts
left over, unless you’ve replaced something
with a new part. Don’t over tighten screws,
stripping out aluminum threads is very easy and its
expensive to fix. Just hand tighten everything so its
snug, and you’ll be okay. Your done!!
Don’t forget to rechrono your marker before
you play with it, and always keep safety first!!!