The ability to accept so many mods and accessories is one if the hallmarks of Tippmann paintball markers, with the most popular being the shoulder stock. There are many styles to fit anyone’s specific need and look. Stocks require the marker to be taken apart to install. While Tippmann 98 Customs and Custom Pros are simple in their design they are a little bit of work to disassemble/ reassemble and can be a bit confusing to the beginner when doing maintenance or installations for the first time. Since one of our most common tech questions we receive via phone and email is how to install a 98 Custom stock I decided to try out my new camera and do a photo breakdown.
First, do go over the exploded-view schematic of your particular model in the owner’s manual. These can be downloaded and printed from Tippmann’s website if needed. Familiarize yourself with the parts and names.
Second, prepare your work area. I like to lay down an old bedsheet or towel to work over. It keeps oil stains and grease stains off the table and prevents small round parts from rolling off onto the floor. Have some rags or paper towels handy to wipe up any oil. Make sure there is plenty of light and have all the tools you’ll need handy. The less you have to keep getting up the less chance you will bump the table and have parts go everywhere! Safety glasses are not a bad idea either. I’ve had a small spring pop out and nail me in the eye before so its better to be safe and not need an eyepatch.
Most important… MAKE SURE YOUR MARKER IS COMPLETELY DEGASSED! Remove your air or CO2 tank and dryfire the marker one or twice to ensure there is no pressure in the valve. I cannot stress that enough.
Disclaimer: I am not responsible for any damage you may do to your marker by accident. Go slow and take your time, not forcing anything that seems stuck. If you are unsure what to do, please take your marker to your nearest friendly neighborhood paintball shop!
Note: The marker in the following photos is a 98 Custom ACT with Response Trigger
Okay, got your work area set up and the marker degassed? Take off the barrel and any other bolt-on accesories like sights. Leave the feedneck latched in place, it will help hold the frontsight latch spring in place later. With your 1/8th Allen key remove the ASA screws from under the bottomline ASA and set them aside.
Now remove the five body screws… one at the base of the grip, two by the reap cap, one just forward of the trigger and two at the frontsight and foregrip. Slide the foregrip out from the bottom and set aside.
Now comes the tricky part of the procedure. Gently separate the two body halves and lift the top one away. Don’t yank them apart as this tends to dislodge parts and send them flying.
Take a look at the front sight area. Remember how I told you to leave the feedneck attached? Thats because the little horseshoe-shaped spring under the frontsight latch (circled in blue) is easily the most lost Tippmann internal part. The ball detent (circled in red) should be in place as shown. If installed backwards the marker will cycle erratically or not at all.
Take a good look at the sear and trigger group. That big silver cylinder behind the trigger is the piston for the Response trigger system. Note the placement of the silver pins through the trigger and how they guide the sear. There is one black pin (circled in red) that the sear pivots around. Always make sure the black one is in this location because it is hardened steel, designed to withstand the abuse of the sear slamming against it. If you put any of the other pins here they will eventually bend and break from stress. See the sear sping circled in blue? Pay close attention to it because it has a tendency to pop out of position. It should be seated down snug in its guides.
Since this is an ACT (Anti Chop Technology) model there is a second spring set between the rear bolt and reap cap. Note the placement of all springs, pins and the linkage rod. Lastly, note how the square bottomline nuts sits snug at the base of the grip.
Next, wiggle the springs and spring guide rod out of the rear cap and replace with your new stock. See how the rear cap and the stock fit into the grooves molded into the body? I like to prop the marker up with the rear cap like a sawhorse in the middle of my work. Don’t forget the guide rod or your springs will get destroyed! Look everything over and make sure all parts are snug and in place.
Now gently place the top body half back, slowly working it down into place so the internal parts do not dislodge. Screw in the frame screw through the frontsight first, snug but not so tight that the latch cannot be depressed, then the other screws. The two screws by the stock are the hardest to do because the plastic of the stock is typically a bit oversized to ensure a snug fit. Give it a squeeze if the screws do not catch at first. If hand pressure is not enough, simply clamp it in a bench vise or use a padded pair of vice grips to press it into place.
Reattach the bottomline ASA and viola…. you’re done!
If you have the new Platinum Series 98 Custom the whole procedure is even easier. The Platinum is designed with three pieces to the clamshell body so only one section is lifted up so there are less pieces to be dislodged.
Note: An Ultra Basic Non ACT model is used in the following photos.
You do not have to take off the top rail and you can take the feedneck off if you wish because only the rear body section is being removed. Otherwise the internals are the same and follow the instructions above.
Hope that helps. Many people are intimidated by Tippmanns due to the number of parts but really they are a very simple machine. Just go slow and remember how everything goes into place. Tippmanns amazing reliability and build also means that you don’t need to do a complete strip down maintanence after every day of play like other markers! Any other questions about Tippmanns just give us a call.




If you’re reading this, then you’re probably a paintball player. So am I, going on 20 years now. Ever since my first game in 1987, I have been involved in this crazy sport of ours as a player, marker tech, player, referee, player, salesperson, player, store manager, player, buyer for Paintball-Online.com, and a player. Why do I mention being a player so many times? Because that's what makes me qualified for the job that I do in choosing the products that we sell. I love my job and get to see, test and experience all the cool new toys, trends and changes. This paintball blog is to give you a view into the huge and crazy world that is paintball - in all its forms.