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About GSO-Geko

  • Rank
    Adv Member

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  • Airsofter since
  • Country
    United States
  1. Yes. Just like the OEM valve it leaks if you don't lube it up properly and REALLY tighten those screws. I've tested it at 130 PSI for a full shell with no problems. But I don't run it at that pressure. 100 PSI out of my HPA tank is getting close to 400 FPS.
  2. GSO-Geko

    Marui M870 Fix and Tuning Thread

    http://shop.ehobbyasia.com/blackcat-replacement-spring-set-for-marui-m870-shotgun-mechanical-box.html#.VEbtfPnF98E Replaced the feed arm springs with those from this set, 3 and 6 shot now work. Replacement springs in both of the Blackcat sets are much stiffer than the originals. Set pictured replaces all the springs inside the frame. Alternate set replaces all the springs between the frame and the body.
  3. GSO-Geko

    Marui M870 Fix and Tuning Thread

    I have experimented with mine a bunch, tried shimming the selector up and down, replacing the spring, etc. I even have the Pro Arms Aluminum Nozzle set and Loading Arm. Nothing fixes this issue. But rest assured, if I do manage to figure it out or (more likely) someone else does, I will post it here ASAP, as I would hope anyone else would too.
  4. As a dude who makes his own kydex stuff, I can tell you that holster is extremely overpriced. The mount is maybe $15 if you buy just one (as opposed to 1000 of them at wholesale), and that's less than $1 of kydex if you buy in bulk. The only factor is really manufacturing time, but I think they probably have that down pat, unless they pay their guys $50 an hour. Definitely hold off for until a replica comes out. Or until I make one.... pic related.
  5. GSO-Geko

    Marui M870 Fix and Tuning Thread

    Could be any number of things. are your loading nozzles aftermarket?
  6. GSO-Geko

    Marui M870 Fix and Tuning Thread

    New and Much Brighter take down video. Sorry for the delay everyone! https://www.youtube.com/watch?v=ACqyBNpl_kg&list=PLPOpqBVMxBHsRwsQAXT3SCEJrx3KkxrZT
  7. GSO-Geko

    Marui M870 Fix and Tuning Thread

    Loading Arm Fix So my feed arms finally broke... kinda. The posts on either side of it are bent down slightly, this means that the loading arm doesn't get pushed down enough to allow bbs to feed. And so workbench time. First step is to remove the posts themselves, but not completely, we need a location for the guide hole. Guide hole time. Slowly working my way up the bit size to completely remove the last post stump. I used a 4mm screw with the head trimmed off. Boom. Fixed.
  8. GSO-Geko

    Marui M870 Fix and Tuning Thread

    LOST BARREL BRACKET FIX So if you're like me, you use this gun a lot. And during use sometimes the black plastic bracket at the end of the inner barrels will fall off. And sometimes you will notice and find it, other time (non-plural) you will not. This is more of a problem with the SAT brand shorter barrel, as I think the internal dimensions are slightly wider. However, electrical tape fixes everything. First attempt was with a 4 layer think wrap around all three barrels. This made it so there was virtually no spread on the bbs out to 100 feet, or around 32 meters. While this allowed me to live out my dream of being like those guys that get around sniper limit servers on Battlefield 4, I needed the spread back. Thankfully with calipers and careful cutting you can wrap a 49 mm length of electrical tape around a single barrel almost exactly twice. This put the spread right back where it should be. And has just enough pressure against the inner wall of the outer barrel to keep them stable. Putting rails on the stock foregrip I purchased a G&P railed foregrip, but I found it to be too heavy and loose. Therefore, a rail on the stock grip became the best option. Using a G36 rail set I bought on ebay, first came attaching the rail sections for measurement and pilot hole marking with a silver sharpie. With the pilot holes drilled, I widened them out to accept an M3 screw. And countersunk the inner surface of the foregrip to accept the screw heads. And done. It's very sturdy and easy to do. Plus light enough not to ruin the run-around-all-day with it vibe. Picture above of full shotgun displays the finished result, and no, that's not how I run it.
  9. That's a chamber leak. Take it apart, lube the chamber orings and you're good to go. NEVER EVER EVER EVER EVER force the action. It will break. And that is your fault for FORCING THE ACTION.
  10. I totally removed the lever that makes the 6 shot mode happen. Works really well now.
  11. Understandable. I've been using mine with the metal nozzle for a while now. While I won't guess about what causes the original error leading to nozzle breakage, I can tell you that when that malfunction happens now, the loading action cannot finish. This causes the pump to stick in place a centimeter or two before returning completely forward. To clear the jam, all you have to do is remove the shell, and work the action to fire the left over bbs. This happens every couple shells, doesn't bother me too much. And I've checked the internals to make sure, everything else in there looks fine. I do wish the product just worked though.
  12. Well, you can either buy a plastic nozzle that, due to the design of the feed system, will likely break. Or you can buy an aluminium one, which cannot break.

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