This mod is definitely the cheapest way to improve performance. All you'll need is a few things from the hardware store:
- 1000 grit sandpaper
- Clean, soft rags
- Soap and hot water
- Aluminum polish
Note: Polishing your internals can severely cripple your paintball marker and render it useless if done incorrectly. Further more, attempting this mod voids all warranties attached to the marker. You have been warned.
Note: If you're using an after market or stock Delrin bolt - Do NOT attempt to polish it! Be aware of any "special" internals that are similar. If you do not oil it it's safe to say it probably should not be polished.
The parts that you will be working on are the bolt and striker. Possibly the guide pin and sear as well, but you don't have to/it may not apply to your marker.
At this point I'll turn it over to the pros who have posted well written and detailed guides:
Read through both of these guides to get a feel for the mod before you continue.
This one uses examples from the Ariakon Sim-4 and ACP 2.0 pistol written by Sgt. Slaughter of the Ariakon forums: http://forum.ariakon.com/forum_posts.asp?TID=6839&PN=1
Here's another for the Tippmann 98 Custom specifically from Breene at Model98.org: http://model98.org/mods/polishingint.php?
You'll have to register and sign in to view Model98.org's guides, but it's well worth it for anyone looking for creative mods for an M98. I'll cover more of their mods later as I attempt them myself so I can give a proper review.
Note: The Model98.org guide recommends a dremel tool for the sanding. If you feel you can control a dremel and not create any flat spots, go for it. Personally, I would only suggest using a dremel for the polishing, but I do that by hand as well. But that's only because I don't always have a dremel available.
After you have your internals sanded, polished, and re-oiled, enjoy the smoother operation of your marker. Every 4 uses or once a month you'll want to re-polish, but NOT re-sand.