WE M16 Open Bolt Issues

[Rotting]

Having a couple issues:

1) The air nozzle keeps breaking. The C-shape protrusion keeps breaking apart in the same spot. I've gone through 3 nozzles now, can't figure out what is causing the issue. I've read a few things stating that it is being caused from overloading the mags, but I only ever load 30, never the +1 or +2 that can fit. Note that I've only ever gamed this rifle once and I've broken 3 air nozzles, so I'm assuming I'm doing something very wrong or the rifle is doing something very wrong.

2) Ridiculously poor FPS with an NPAS installed. Tested it at a recent game, was firing 270FPS. Adjusted it all the way both ways to make sure I was adjusting it correctly and 270FPS was the highest speed it could achieve, however going back to the stock piece that the NPAS replaces, it goes back up to 370FPS (still much lower than when it was BNIB at 420-440). Not sure if this is related to the cracking of the C-shaped protrusion of the air nozzle or not.

3) Not locking back after last shot is fired. No clue what could be doing this except possibly the internal piece that is supposed to catch it being worn, but I don't know where or what that particular piece is/looks like, so I don't know how to troubleshoot. For all I know this is also related to the air nozzle being cracked.

Any insight would be much appreciated. If a photo is needed to show what I mean about the air nozzle cracking I can provide one.

[Towe1ey]

There are a few things you could try. For the nozzle I'm not 100% sure how to alleviate the C-shape from breaking as I've yet to experience this for myself. Have you taken a look at the nozzle guides lately? Perhaps they're worn causing too much play in the nozzle itself. I'm sure somebody could help out a little more than I could there...

As for the bolt not locking back, there are a number of fixes to this problem. I've had great success with Kullwarrior's method. Taking a look on YouTube should show you what you're looking for. It's basically taking the right sized AEG shims and inserting them in with your bolt catch release lever to minimize left and right play in it.

[Rotting]

The nozzle guides don't appear to be worn down. Like I said, the rifle is still pretty new, wouldn't expect much wear and tear on the guides. Also worth mentioning that it's always the same bit that breaks. If you point the loading nozzle at you and look at it, it's the 12o'clock and 2o'clock area. 2-3o'clock doesn't seem to be breaking though.

I'll take a look at the shimming video some time this weekend to fix the no-catch issue.

Edit: I'm also still quite concerned about the NPAS having such poor performance. Hoping someone with a lot of WE tech experience and knowledge can assist with it.

[audi_bhoy]

For the bolt catch, I've had good sucess sticking a shim under the bolt catch, where it meets the mag's follower.

[Ross]

The nozzles break because they are junk. As a troubleshooting step, you can rule out the overloading of magazines by charging the gun first and leaving the chamber open before inserting the mag. If you do this every time you reload, and the nozzle still breaks, then you know it's not from overloading.

In some cases the npas can cause more problems than its worth. When you have the npas installed, less gas is used to propel the bb forward, and more of it is expelled outward, freezing internals and adding more pressure to the recoil operation.

Which means more chance of cracked nozzles.

If your current installed nozzle is cracked, then it is most likely the reason you are shooting 370 fps instead of 410. Also huge factors is temperature. If you are chronoing your gun outside and it's cold, your fps will be reduced. A cracked nozzle would also be the reason you are shooting 270 fps with the npas wide open.

The bolt not locking back could be a problem with the bolt catch or the bolt carrier itself. I find the shimming method to work well.

[Kos-Mos]

I have never seen the top part breaking.
That part is not doing much normally, the bolt carrier and receiver are supposed to keep all that center.

You either have a broken/badly aligned hop-up unit or bolt.
Or your bolt carrier is crooked.

You should try to slowly let the bolt move forward and see if it stops before being closed.
Also take a look at the top guide (the one that is under the fake operating rod).

Might be as stated before, bad bolt carrier, or maybe the top guide/left guide is badly molded. Can also be the mag catch that pulls the mags too high, but you would probably break loading pins (bottom part) of the nozzle way before the top.

[Rotting]

Alright, thanks.

I'll take a look at everything to ensure everything is aligned properly. I did change out the barrel, so it could be possible that on reassembly I missed something. I'll inspect everything to make sure there's no poorly molded guides and check for any discrepancies. I'll get back to this thread this weekend if I find anything concerning.

Also, what would be the recommended upgrade route? I know the ra-tech rubber is garbage, I can't get a consistent burst to save my life with it, but not sure about any other upgrades. Mainly just looking to replace functioning pieces that take on a lot of damage over time to steel equivalents, but have no idea where to look or where to start. (I'm still pretty green when it comes to GBBRs).

[MaybeStopCalling]

Functionality wise, I replaced my bolt catch with a steel one and my trigger group with a CWI one. Everything else improved durability, but these are the ones I recommend at a minimum. An RS magazine release will improve the reliability of your gun's bolt catch as well.

[Kos-Mos]

Well, I prefer to run my guns stock (since none had any issues yet).

But you can install any rubber made for TM VSR-10.
KingArms RED is a good choice.
Firefly rubbers are also good.
I prefered the Promy ones, but since you had issues, it might confirm that something is out of line.

Also, you won't get accurate burst, this is GBBR, not AEG. Auto is meant to suppress more that hit targets.

[Danke]

Pictures?

[Rotting]

Seems FPS is back to normal after replacing the nozzle, will be putting the NPAS back in soon to see if it will function properly as well.

Also, by "accurate burst" I mean 3 shots and none of them are grouping properly at all. Have one go nicely straight, second will go way up, third will go way down. Very unpredictable. Even doing semi-only I don't seem to see much accuracy. It looks like it's just the hop-up being odd though. On the x-axis I'm staying closely grouped, but the Y-axis is terrible.

Took a look inside around the hop-up chamber to see if there was anything stuck in there causing the breakage. Nothing was found. Went back to look at the previous nozzles that all broke, seems i was wrong about where it breaks. It's still on the C-shape protrusion, however isn't not always in the same spot. Sat down with the new nozzle installed and gently pulled the charging handle back and forward to see if it's snagging on something, but not seeing, hearing, or feeling anything.

Also noticed that when the charging handle is pulled back, the carrier fully retracts, however the nozzle itself remains somewhat forward. When I got the rifle brand new, this didn't happen. The air nozzle would retract fully with the bolt carrier. Wondering if the rails just need to be greased?




EDIT: So for the hell of it, I put the original loading nozzle that came with the rifle back in. It's missing a piece on that c-shape area, but still functions just fine. The one thing that gets me is that it glides perfectly in the bolt carrier. All other loading nozzles I have do not glide nicely and get hung up about 1/2 way back and stick (if you put your finger in through the ejection window, a light tap on it will knock it all the way back though). I installed the NPAS back into that one and tested it. Firing approx. 385-400FPS. So my question is has anyone else had issues with the replacement loading nozzles being much too snug? The original nozzle that came with the rifle broke because of a jam that I didn't properly clear out, which was my fault. However I'm wondering if the other two loading nozzles broke because they weren't retracting fully with the bolt carrier and as a result on return were not properly seating due to misalignment from being sticking out so far.

Also I saw the bolt catch modification video. Currently don't have any shims, but manually played with the bolt catch to make sure that it indeed needed to be shimmed and that definitely was the problem. Seems I'm also able to put the rifle in safe when it the rifle hasn't been loaded. When I originally got it, that's how it was. Now it seems I can go into safe whenever. I have no idea what goes in in the trigger grouping, so I have no clue what to look for.

@MaybeStopCalling; Where did you find the CWI parts from? I tried searching for them but couldn't find anything. Not sure if I'm just blind or what.

[SF_Chewy]

With the nozzle, are the guides on the new ones too long? Perhaps sanding them lightly will help.

You can find CWI parts from bbdragon.com.tw

Great parts, I replaced my charging handle and my trigger grouping with these steel parts. Their stuff is more to spec than Ra-Tech from what I've found

[Kos-Mos]

Originally Posted by Rotting

Seems FPS is back to normal after replacing the nozzle, will be putting the NPAS back in soon to see if it will function properly as well.

Also, by "accurate burst" I mean 3 shots and none of them are grouping properly at all. Have one go nicely straight, second will go way up, third will go way down. Very unpredictable. Even doing semi-only I don't seem to see much accuracy. It looks like it's just the hop-up being odd though. On the x-axis I'm staying closely grouped, but the Y-axis is terrible.

Took a look inside around the hop-up chamber to see if there was anything stuck in there causing the breakage. Nothing was found. Went back to look at the previous nozzles that all broke, seems i was wrong about where it breaks. It's still on the C-shape protrusion, however isn't not always in the same spot. Sat down with the new nozzle installed and gently pulled the charging handle back and forward to see if it's snagging on something, but not seeing, hearing, or feeling anything.

Also noticed that when the charging handle is pulled back, the carrier fully retracts, however the nozzle itself remains somewhat forward. When I got the rifle brand new, this didn't happen. The air nozzle would retract fully with the bolt carrier. Wondering if the rails just need to be greased?




EDIT: So for the hell of it, I put the original loading nozzle that came with the rifle back in. It's missing a piece on that c-shape area, but still functions just fine. The one thing that gets me is that it glides perfectly in the bolt carrier. All other loading nozzles I have do not glide nicely and get hung up about 1/2 way back and stick (if you put your finger in through the ejection window, a light tap on it will knock it all the way back though). I installed the NPAS back into that one and tested it. Firing approx. 385-400FPS. So my question is has anyone else had issues with the replacement loading nozzles being much too snug? The original nozzle that came with the rifle broke because of a jam that I didn't properly clear out, which was my fault. However I'm wondering if the other two loading nozzles broke because they weren't retracting fully with the bolt carrier and as a result on return were not properly seating due to misalignment from being sticking out so far.

Also I saw the bolt catch modification video. Currently don't have any shims, but manually played with the bolt catch to make sure that it indeed needed to be shimmed and that definitely was the problem. Seems I'm also able to put the rifle in safe when it the rifle hasn't been loaded. When I originally got it, that's how it was. Now it seems I can go into safe whenever. I have no idea what goes in in the trigger grouping, so I have no clue what to look for.

@MaybeStopCalling; Where did you find the CWI parts from? I tried searching for them but couldn't find anything. Not sure if I'm just blind or what.

Make sure that you assemble the nozzle and piston properly.
There is a mold mark on top of the nozzle. The "equivalent" mold mark on the piston should be in the bottom.

That caused me some binding.

[Rotting]

The nozzles were definitely assembled correctly. Always double-checked before I locked them into place to make sure the tab wasn't being crushed.

Found some of the CWI parts on bbdragon, but I can't seem to find any of the trigger parts or steel machined parts. Pretty likely I'm looking in the wrong category since the site is rather harsh on the English. Did a site-wide search for anything manufactured by CWI and still no trigger parts. Any help? :/

Tried searching around to find an A+ REAPS, since I've read nothing but good about them, but they seem to be out of stock or just not stocked period in all the stores I know in Canada. :/

[Rotting]

So I picked up the Hephaestus trigger assembly (found that their set had better review than the RA-Tech assembly) and have it on the desk for this weekend to install.

Also picked up the RA-Tech steel bolt catch. Installed it and threw in an empty mag (made sure it wasn't checked for dry-fire mode), pulled back the charging handle, and didn't lock. Not too sure what to do here. I have a washer on each side of the bolt catch but that doesn't seem to be doing anything. There is very minimal play, just enough to allow it to freely move. Any suggestions?