Excellent your video on HW100 maintenance. I'm Brazilian and I have an HW100. Here I don't have much information about maintenance and you helped me. Obrigado
I find these videos oddly soothing. Oddly because I usually have a stress reaction to anything weapon related. Soothing because my dad's former Army, and he can take his weapon apart, clean it, and put it back together. I find mechanical skill soothing. 💜
Right. The "leaving the gun pressurised" issue. MK1 hw100 (see my hw100 power up vid) has brass fittings where the air bottle screwed in. Repeatedly unscrewing the air cylinder (as you had to do before quickfill) wore the threads out very quickly causing all sorts of problems. This was finally addressed i think in the MK3 or 4 which were fitted with steel inserts. So the trade off was, leave the gun charged and save the threads and once every few years change the breach block/seal washer as opposed to empty / fill the bottle every time you want to use the gun. My HW100 is what, 20 years old? I've just this last hour fitted a new seal on the breach block as it has a slow leak and that's the 3rd washer it's had and i leave it charged and it went two years without being used during the great plandemic and Convid19. They are great guns and need very little maintenance. Just a wipe with an oily rag on the stock (walnut oil) and a spray with a light machine oil on the moving parts and that's it.
Are you sure it's the small red oring that fails when you repeatedly remove the air cylinder? Another video claims there's a large oring (part# 2674b) underneath the removable brass part that gets crushed. I currently have a leak that was not fixed by replacing the small oring, and is definitely due to something in the receiver because the air cylinder holds pressure indefinitely, but empties in a few minutes when on the gun.
Is after market cylinder or the original one? If its after market one make sure the air is out They are normally tight the first time you remove them..