Nope - not user servicable. It's a sealed optic from Hensoldt, so if you take it apart, I'm sure HK will no longer offer any kind of warranty replacement.
I remember hearing from somebody here awhile back that they contacted HK-USA and they sent it in. HK-USA replaced the optic with a clear one, so that may be an option for you.
If you go that route, let us all know how it goes. My 3x Export sight (no red-dot) has very minor specks and I kind of overlook them when shooting. You really only notice it when shooting at plain white paper, as they blend into any other shooting background.
That reticle pattern is truly innovative (considering the Steyr AUG 'donut-of-death' from the 80's), but the FOV is so narrow and the ocular distance is so short that it makes it hard to use effectively. I've also had some issues with drifting zero with my 3x carry-handle optic and recently moved on to KAC long rail and flip sights (600m rear). These are matched with a Trijicon TA31RCO-M4 and works great.
I don't think I'll be going back to the carry-handle optics as much as I like the 'classic' G36 look. The accuracy potential is really improved greatly by going to a better sight. Good luck,
I sent HK Customer Service an email asking if I can send them the scope to be repaired. I read another a posting from another member on this board that did the same and he received it back nice and clean.
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