Shady's GBB teching thread

Discussion in 'Gas Powered Guns' started by Shady, Dec 28, 2013.

  1. Shady

    Shady Administrator Staff Member Administrator Moderator Lifetime Supporter

    Well, all the cool kids are making their own teching threads so why not. In this thread I will be chronicling all the builds, repairs, etc I do for my customers as well as my own builds (rare as they have become). I will also be covering my flipping projects, buying broken guns, fixing them, then selling them. Tomorrow I will start posting pictures of the various projects I have going on right now including sealing leaking GBBR mags, replacing the hammer in FE's G17, a hicapa build that has been a particular pain in the rear, and a 1911 repair/build that has been giving me nothing but problems for over a year and a half.
    Benjamin Thurston likes this.
  2. TheLost

    TheLost Conductor of the Poop Train Supporting Member

    I'm really excited to see this thread grow, dropping a sub!

    Maybe we'll be able to reference certain people to this thread when they question you are one of the best GBB techs here on the forum ;).

    This should be awesome, can't wait to see your guns Shady.

  3. Magpulman

    Magpulman Active Member

    This is a much needed thread. I feel like i'll learn a lot about GBBPs. And i need to learn about them.
  4. Thestig

    Thestig Some say... Supporting Member

    Colorado Springs and Southern California
    Dropping a sub. I can vouch for Shady's ability to transfer knowledge in an easy and understandable way. This thread could be special.
  5. Shady

    Shady Administrator Staff Member Administrator Moderator Lifetime Supporter

    Well, I've taken a lot of pictures of the build I'm working on, those will be posted tomorrow. Right now I'd like to go over my teching area, tools, and some tricks I've picked up.

    First, my desk. It's a tad messy but here you go:


    On the left is my organizer full of spare parts, and in front of that is a gearbox I kinda gave up on. In the middle is my work lamp (has 2 outlets which is handy when I need my dremel). On the right is where I keep my gases and lube.

    To the tools:


    I try to keep my tools at least semi-organized. I have screwdrivers of every head and size imaginable, every Allen wrench I can get my hands on, and a multitool. I also have wire cutters (great for cutting small springs) and pliers. I always keep a sharpie for keeping track of parts and labeling, and a telescoping magnet with flashlight, as parts get dropped and I'm too lazy to pick them up. This is also where I keep my attachments for my dremel.

    The best trick I've learned is that, in order to keep small parts from getting lost, drop them in an empty pill bottle:


    Thanks to the lockable lid and small size, these containers are great for keeping those small parts you really don't want to lose.
  6. Finalencounter

    Finalencounter Duke of Penguins Supporting Member

    Yay! Go Shady! Woot!
  7. cmsadio15

    cmsadio15 Member

    New Orleans
    ^.^ that gun on the desk! Dropping a sub and can't wait to read about the hi capa.
  8. nstein54

    nstein54 New Member

    Shady, do you have much experience installing metal kits on TMs? I am ordering one soon, and I don't have the knowledge to install it and I don't trust my local tech to do this. You seem to be the most experienced pistol tech, and would gladly pay you to do so, if you know how. Thanks
  9. havocm4

    havocm4 Active Member

    Finally! This thread was long needed. Dropping a sub, can't wait to see what's next.
  10. Shady

    Shady Administrator Staff Member Administrator Moderator Lifetime Supporter

    Depends on the kit. 1911s and Glocks are easy, M9s and others are a tad more difficult and would require more time.

    Finalizing my write up for the hicapa build tonight, hoping to post tomorrow.
  11. nstein54

    nstein54 New Member

    Its a MEU 1911 and I am planning on a PGC Metal Kit. Thanks alot
  12. Shady

    Shady Administrator Staff Member Administrator Moderator Lifetime Supporter

    Then yes, that will be relatively simple.

    Well, this is my first write up of a build so please bear with me. Feel free to leave any comments or questions you may have of course.

    I was contacted by a member wanting me to fix and upgrade their WE 3.8 hicapa. Upon receipt I test fired everything. On test fire, the slide would not blow back all the way, instead getting caught halfway back instead of finishing the cycle. I also found that the gun must be cocked in a certain way otherwise it would catch and be hard to cock. I deduced, after feeling some grinding when cocking the gun, that the blowback unit (BBU), was sitting too low. Pretty easy fix. I informed the owner of the gun what the problem was and he ordered the following parts:


    Upon receipt of the parts the first thing I went for was the high flow valve, the easiest part to install. Or so I thought. Turns out, as you can see in the following picture, the new valve (right) is much shorter than the original (left):


    Because of this, the valve knocker was unable to reach the valve and would not release gas, so the part was scrapped from the upgrade list after consulting the owner.

    The next part I decided to install was the spring set. Given that stock springs in a 3.8 hicapa are around the 120% area and the upgrade springs chosen by the owner were 170%, I was a little leery of this. As you can see from the pictures below, the upgrade springs (right) are far longer than the stock springs (left):



    Due to this, and the gun being smaller than the standard 5.1 that the springs are designed for, the springs required modification to work correctly. In order for the hammer spring housing to fit back onto the grip, I used my dremel to remove 3 coils from the spring.

    The recoil spring was also much longer than the gun could handle. In the original form, the slide would not have enough room to completely compress the spring when blowing back, resulting in no feeding. In order to fix that, I removed a total of 5 coils, again using my dremel, from the spring. Taking it from this:


    To this:


    (both pictures taken next to the stock spring)

    Next to install was the new bucking/inner barrel. This install was extremely straightforward and probably the simplest part of the job. Or so I thought. Thanks to WE's poor quality, one of the main posts of the hop up chamber broke off on reassembly, as you can see here:


    Luckily, I had a spare hop up chamber and was able to swap the parts easily.
    Stock barrel/hop:


    New barrel/hop:


    Next project was replacing the stock nozzle (left) with the new Angel Customs nozzle (right). This was a challenge as the internals of the nozzle had to be transferred over, using the tiny little screw you can see on the new one. Exceedingly frustrating to work with.


    Due to picture limit, this write up will be continued in the next post.
    Last edited: Jan 6, 2014
  13. Shady

    Shady Administrator Staff Member Administrator Moderator Lifetime Supporter

    Next was the blowback housing and the piston head. You can see the stock housing on the left and the Angel Customs housing on the right.


    The Angel Customs used a different piston style than the stock housing, so the piston head was set aside at first:


    Come to find out, the AC housing did not properly fit the hicapa slide and was therefore put aside. This mean that we could now replace the stock piston head (first picture) with the new piston head (second picture, seen assembled on the piston).



    Once the new piston was assembled, all that was left was final assembly. Unfortunately the nozzle return spring had become warped during the trial and error process with the AC housing. After contacting the owner, he sent a new one and I was able to complete the assembly. You can see the new spring (left) next to the warped spring (right):


    Here you can see the blow back unit completely assembled:


    During reassembly I noticed the stock slide catch was worn down and would no longer stay in place, so it was replaced with a spare slide catch I had laying around, an extended version. Once I got the gun completely assembled everything worked smoothly. Due to the increased recoil spring vs the short slide the gun had a quick return time on the slide, allowing for faster follow up shots. The trade off, however, was incredibly reduced gas efficiency. I then tuned the hop up for .28s (weight the owner requested it be tuned to) and chrono’d the pistol. In 50ish degree weather with propane the pistol fired a max of 300 FPS with a .20 BB and a low of 279 at the same weight.

    Finished product:


    Even with all of the issues with fitment and such, I quite enjoyed doing this build. I hope you enjoyed reading about it.
  14. James2jones

    James2jones New Member

    Just dropping a sub, I figured it'd be good to learn a thing or two about this stuff.
  15. COASTsniper1

    COASTsniper1 Active Member

    Nice. I'm subbing to this :D.
  16. killerbee

    killerbee New Member

    Very much a welcome thread. The forum has a ton of info on aeg's but not nearly enough on GBB pistols. Thanks for sharing your knowledge.
  17. AAAOA

    AAAOA Active Member

    Dropping a sub, I have a feeling I will need this thread in the near future.
  18. Sniper272

    Sniper272 Active Member

    Subbing to this don't see many like this.
  19. hardcore247

    hardcore247 New Member


    Me to!

    I have a question...

    How can I add a threaded tip to my kjw government edition m9? I really would love to add a suppressor so this is kind of a must, thanks!
  20. Shady

    Shady Administrator Staff Member Administrator Moderator Lifetime Supporter

    Buy and install this:

    I would love to hear what you guys thought of the write up, I should be doing more soon.