I've yet to have a DM noid gasket fail. It does happen but...
Everything else is basic buna orings. Well, UR originally... but I'd just use buna. Debatable. UR rings disintegrate and turn into "eye booger" consistency and color, both dry or gooey. You'll see....
Change the 007 in the HPR and the 006 in the LPR before any air goes in the gun. Both have 'tricks' to changing, find them on PBN (pencap install, "shooting the LPR out" --- SAFELY).
Open the bolt up and change any "eye booger" orings over black buna, lube it up. For ALL of these orings you have to get ALL of the old one out. I use compressed air and a pick as needed.
Don't mess with the noid. Be careful with your eye ribbon, and, the wiring for battery/microswitch, both get brittle. Get basic black orings, not colored, they shoot better.
This ^ will get 95% of old matrixes back on a field. Good luck. Post then PM me if really stuck I'll help.
Last edited by mueller : 02-27-2017 at 08:43 AM.