Wait, stop buying things. Let's figure this out - it's not tricky and this has gone on too long. I thought the
parts list above was clear but maybe I've not made it clear enough.
What do you have right now? Send a photo of the fittings you have because your updates are useless without them.
You
don't need a 6mm to 1/8 NPT unless you're talking about the elbow itself, which is 1/8 NPT, then a 90o turn, then a push fitting for a 6mm macro/pneumatic line. If you are still trying to make that threaded one work then don't - it's bulky and plain and simple is the wrong part. At best you're going to need to probably cut more material out from the rubber stock pad if you use it, and the adapter is going to add extra bulk. At worst it'll stick out the back and make your gun ugly and uncomfortable to shoulder.
You need:
- 1/8 NPT to 6mm push fitting elbow (metal if you can, plastic if you can't)
If it's metal and BSP, not NPT then it's no good for you unless you have a BSP tap and haven't already tapped it to NPT (which it sounds like you have)
- As this is going to be behind the stock then there's probably no issue at all with plastic - I just prefer metal for longevity
- Swivel elbow is a plus as it'll allow you to completely torque it into place without the need for a washer/shim, but frankly if you're using a pneumatic sealant then you can get away with under-torquing it anyway
[*]40cm of 6mm macro/pneumatic tubing
- Usually you'll need to buy it in 1m+ lengths, but cutting it is easy
[*]6mm push fitting to male quick disconnect
[*]Adhesive shrink wrap (optional but recommended)
You can buy this all off eBay for <£16. If you're still having trouble with the
6mm push fitting to male quick disconnect then I can confirm that I have a couple spare. PM me if you want me to send one.