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Lupus78

WE Gas Blow Back M4A1 Carbine

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I picked up a Stinger hopup and a few misc. parts; along with a tip that the bolt assembly of my 1st gen WEM4 might be causing my problems with nozzle breakage. Does anyone have an old M4 with an upgraded bolt; or any thoughts on the old bolts being out of alignment? I thought that alignment had more to do with positioning of the valve rod.

 

Is the current bolt assembly in stock anywhere?

 

Did your nozzles break with propane or CO2 ? My old v1 still goes strong, i don't think the BCG could be misaligned or you would see it in the BCG itself and on the upper receiver internal walls/brass chamber, there would be metal dust everywhere and huge wear on them.

To me most nozzles breaking are due to part #117 and cause of that all my guns now have a modified part #117/#40.

 

a) Got me a spare part #117 ( M4 ) and removed some material from it. If you look inside that part you'll see that it's "ribbed", remove material just enough for the internal walls of it to be smooth. Test manually with a nozzle, you'll see that the nozzle slides with much less friction and goes in and out smoother.

I then used a cone shaped grinding bit as i found easier to give part #117 the shape you want with it, i even added a "crown" to the entrance of it so that the transition between part #117 and the entrance of the brass chamber would be smoother, if you look inside the brass chamber you'll see that there is a difference in height between those parts and if the nozzle isn't exactly aligned with it, it adds stress on the nozzle tip when it hits part #117 itself.

 

Just by doing this you'll notice that the BCG cycles smoother and there is much less resistance when the nozzles enters and exists part #117. But even with this mod i noticed that there was still some resistance and the BCG didn't cycled completely smooth in it's entire cycle, after watching and testing the complete system manually, it seems that in the middle of part #117, the last "rib" is a bit bigger than the rest ( where the very tip of the nozzle sits within part #117 ) and it "grips" the nozzle ( i believe it's made this way for maximum seal efficiency ).

 

B) What i did was ( since i didn't wanted to disassemble everything again ) was to remove part #40 ( the little transparent spacer on the guiding rod ) and make one myself from a softer material ( i used the silicone casing from an heavy duty electrical cable ) and make an equal spacer but 0.5mm/1mm shorter than the stock one. Comparing the system with the stock and modified spacer there isn't any accuracy/performance difference, the sheer momentum of the BCG pushes the BB the "lost" 1mm.

 

All my guns now run this mod and they function perfectly with a silk smooth BCG cycle. Since i have many extra nozzles i decided to run a simple longevity test with a mod BCG assembly vs a stock assembly on CO2. The stock nozzle broke within 300 CO2 rounds ( broke in half, the front section of the nozzle got stuck in part #117 and had to use pliers and quite a bit of force to remove it ), the modified setup still runs perfectly.

 

I'll try to post some pictures of it the following days to demonstrate exactly what i've made.

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So sorry if someone else here has posted this question: does anyone here has tried the 6.01 Edgi barrel? does it significantly improve the accuracy ?

 

Tx!

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hi im kinda new at this fourm but i have a big problem with my gun , so my friends and i were playing with it but after a while when i shot the gun it wouldnt fire so i pulled back on the hammer to try to reload it but when i pull on the hammer it would fire, i speant around 500 dollars ont his gun please help me solve this issue thanks

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hi im kinda new at this fourm but i have a big problem with my gun , so my friends and i were playing with it but after a while when i shot the gun it wouldnt fire so i pulled back on the hammer to try to reload it but when i pull on the hammer it would fire, i speant around 500 dollars ont his gun please help me solve this issue thanks

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^

All you get is a "click" after pulling the charging handle and squeezing the trigger? Valve knocker (part 61) either binding against the disconnector (part 66) or the disconnector itself is broken. To check if its broken, split your receiver and take a look at the valve knocker. Now, pull on the hammer until it locks and you should also see the valve knocker retract. If it hasn't retracted, try gently wiggling it around in case it just snagged against the disconnector. If it still won't retract, chances are the disconnector is busted. To fix the snagging issue, you have to lightly file down the sharp edges of both parts 61 and 66 that meet each other. Also apply some silicon oil on this area when reassembling.

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Really starting to lose my patience with this money-pit of a gun! Can anyone help with the problems below please?

Today at a skirmish the gun misfed/misfired right from the word go. It fired one round, then started 'collecting' BBs and would spit 6 or so out at a time (even with the hop completely 'off'). I tried various quality brands of BBs and the same happened with all of them, and it happened with all 6 of my magazines.

Just as the problem seemed to cure itself, the bolt carrier then jammed back half into the buffer tube (about half an inch of the bolt carrier was visible from the ejection port) and I could not get it to move forward or backward even with some help, hence I couldn't open the receiver. I had to unscrew the buffer tube and 'wiggle' the bolt carrier around for ages until finally pulling it out. I re-lubed everything and replaced the bolt carrier and buffer tube and now I have two-round burst fire on semi auto!!

If anyone can help or point me in the right direction I'd really appreciate it!

In terms of internal upgrades this M4 just has the NPAS kit, stinger hop kit and the 6.02 chrome barrel. I am running on Co2 if that makes any difference.

Edited by L33

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Actually if you did everything right the first go, its cheaper than spending it on a AGM and upgrading it up from there. WE's are way more durable than the WA system.

 

What you need to get the WE M4 running smooth:

 

1) Modify (bore out) Part 117# - eliminates feed jams, minimises nozzle breaking + cycling without loading rounds

2) Sand down ribs on the nozzle or replace nozzle with the PDW nozzle which has been strengthened and no ribs - same as 1)

3) Stinger hop up - +1 on accuracy and consistency

4) CWI Steel trigger sears and hammer - Minimises hammer wear

 

If you have any other issues it would be firing pin, firing pin cover and valve locker:

 

5) Mod the firing pin or replace with steel firing pin (Mine is the stock part but modded)

6) Mod firing pin cover or replace firing pin cover periodically (Mine is the stock part but modded)

7) Replace with steel valve locker. (Mine is still stock)

 

 

Othe than that its leaky mags which can happen if you don't store your mags with at least a little bit of gas, O-rings and Rubber bits will dry out and shrink.

 

That's it really. That will cover 99% of the issues on the WE M4.

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You're in luck then. The fact that it sometimes does means nothing is broken.

Now refer to the WE M4 parts list:

http://arniesairsoft.co.uk/news2/wp-content/uploads/2008/12/image208.png

See part numbers 61 and 66? 61 is the firing pin that sometimes doesn't go back when you pull the hammer. You can't see 66 right now and you probably don't need to anyway. Now, here's how the parts function. You pull the trigger and the hammer falls. Hammer hits the firing pin (61) and opens the magazine valve. The bolt cycles and resets the hammer, but the firing pin is still forward as it is locked in place by the disconnector (66). Only until the hammer is set all the way down that it pushes on the disconnector which releases its hold on the firing pin and allows the valve to close.

 

What happens in your case, in all probability, is that the contact points between the firing pin and the disconnector have gone sharp and so even if the disconnector is reset by the hammer, the firing pin is still stuck in the forward position. At this point the valve of the magazine is what resets the firing pin but deflects it upwards instead so the next time you pull on the charging handle and squeeze the trigger, the firing pin (being stuck and misaligned) does not hit the valve and all you get is a "click".

 

Here's what you do. Split the gearbox and look at part no. 59. It has two screws on it; undo them. With the plate out, you can remove the firing pin (61) and the spring plus spring guide underneath it. The spring and guide are not in the parts list so keep aware of them. With the firing pin removed, you can see in the trigger assembly a portion of part (66). It's in silver color and sticks out, you couldn't miss it. Now, look at the part where that nub locks against the firing pin. The idea here is to lightly file the edges down so they're not sharp. Don't remove material on the surfaces itself, just lightly round out the corners and edges with a file or bit of sand paper. Clean and reassemble everything back and apply a bit of silicon oil on the firing pin especially on the part where it meets part 66.

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Thanks 3vil1-D4n for the parts list, I'll definately look into modifying part 117 and getting hold of a CWI trigger set.

 

In the mean time, I've done a little more investigation now that I've had a few hours to sit down and look at it. Strangely, I've noticed that it has become very difficult to get magazines to lock into place in the magwell - it requires too much force. By removing the bolt carrier and watching through the ejection port as I insert a mag, I noticed that the rubber gas seal is touching the brass cylinder about 1mm before the mag catch 'locks' the magazine (this happens with all 6 of my magazines) which means a lot of force is put on the brass cylinder to fully insert a mag, which isn't good - I can see the brass cylinder being forced upwards.

I've checked and the brass cylinder appears to be perfectly straight. With the cylinder removed the mags lock into place easily.

Has anybody experienced this problem before? A search on various forums only reveals the M4/Scar mag incompatibility issue due to the raised gas seal on the scar mags, but mine are definately M4 mags (the gas seal barely protrudes from the plastic guide on top of the mag).

Again, any help much appreciated! :)

Edited by L33

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Drop these guys an email, they can get pretty much anything for a WE platform rifle, :)

http://airsoftbuddy....at.php?cPath=32

 

 

They've been out of bolt carriers for a while. Aside from any centering issues it might be causing, mine is badly worn where it contacts the bolt release.

 

The white plastic part on you bolt needs to be as far back as posible, if it is even a littel bit forward the hammer hits it.

 

I wonder if I can put a little adhesive somewhere to keep it in place? Mine tends to creep forward crating a potentially dangerous misfire situation (no bang when trigger is pulled, fiddel with fire selector and gun goes off).

 

I'm liking my Stinger so far, but even with my custom hop nub (cylindrical hobby bead filled with epoxy) I have to run it almost maxed out. I read somewhere that a segment of 2mm thick O-ring about 2mm long makes a good hop nub when used with the Stinger shims.

 

My part #117 seems to be peeling/shredding when I look down the barrel. I ordered another one from ASB along with a fresh lower and some odds and ends. I assume you guys are talking about sanding off the ribs shown here on the wide end:

 

Parts_WE_GR_117_lg.jpg

 

 

Did you also smooth that step out? What kind of bit did you use?

 

And 3vi1-D4n, I couldn't find a photo of the PDW nozzle. What ribs are you talking about?

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L33, can you verify if there is no spacer under the rubber seal by removing the mag lip?

Thanks for the reply - I've just unscrewed the feed lip on a couple of mags and there is no rubber seal below on either, just the square rubber block which seals to the brass cylinder.

I have hopefully just resolved the brass cylinder/mag issue by unscrewing the delta ring and removing/replacing the barrel assembly. It seems for some reason part #114 (inner barrel nut) was not sat flush in the upper receiver?! Strange.

 

The mags now lock into place much easier, but I still have the same problem with feeding/burst fire :( A quick pull and release of the trigger on semi auto 'fires' 2 or 3 times, only the first BB comes out at speed, any others will queue up somewhere inside and either roll out or fire out all at once.

 

I've followed 3vi1-D4n's advice and removed excess material from part #117 by turning it inside out and sanded using a dremel griding bit at low speed. When out of the chamber it allows a BB to pass through with relative ease, but enough to prevent it rolling out of the barrel. When #117 is put back into the chamber, it is a little tighter and takes a push to pass a BB through.

Unfortunately it has not cured the problem though so the cause must be elsewhere.

Edited by L33

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@ kojak : I've used several home-used glue's and the like to keep the white spacer in place but I've not found the right one. Have to find a much stronger one.

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@ kojak : I've used several home-used glue's and the like to keep the white spacer in place but I've not found the right one. Have to find a much stronger one.

 

I just used loctite, never failed me.

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Managed to dig up that old drawing I made:

61.jpg

The part highlighted in red is what the disconnector comes into contact with. The idea is to file down any burrs on corners and the outer edge to reduce friction or any snagging.

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Did your nozzles break with propane or CO2 ? My old v1 still goes strong, i don't think the BCG could be misaligned or you would see it in the BCG itself and on the upper receiver internal walls/brass chamber, there would be metal dust everywhere and huge wear on them.

To me most nozzles breaking are due to part #117 and cause of that all my guns now have a modified part #117/#40.

 

a) Got me a spare part #117 ( M4 ) and removed some material from it. If you look inside that part you'll see that it's "ribbed", remove material just enough for the internal walls of it to be smooth. Test manually with a nozzle, you'll see that the nozzle slides with much less friction and goes in and out smoother.

I then used a cone shaped grinding bit as i found easier to give part #117 the shape you want with it, i even added a "crown" to the entrance of it so that the transition between part #117 and the entrance of the brass chamber would be smoother, if you look inside the brass chamber you'll see that there is a difference in height between those parts and if the nozzle isn't exactly aligned with it, it adds stress on the nozzle tip when it hits part #117 itself.

 

Just by doing this you'll notice that the BCG cycles smoother and there is much less resistance when the nozzles enters and exists part #117. But even with this mod i noticed that there was still some resistance and the BCG didn't cycled completely smooth in it's entire cycle, after watching and testing the complete system manually, it seems that in the middle of part #117, the last "rib" is a bit bigger than the rest ( where the very tip of the nozzle sits within part #117 ) and it "grips" the nozzle ( i believe it's made this way for maximum seal efficiency ).

 

B) What i did was ( since i didn't wanted to disassemble everything again ) was to remove part #40 ( the little transparent spacer on the guiding rod ) and make one myself from a softer material ( i used the silicone casing from an heavy duty electrical cable ) and make an equal spacer but 0.5mm/1mm shorter than the stock one. Comparing the system with the stock and modified spacer there isn't any accuracy/performance difference, the sheer momentum of the BCG pushes the BB the "lost" 1mm.

 

All my guns now run this mod and they function perfectly with a silk smooth BCG cycle. Since i have many extra nozzles i decided to run a simple longevity test with a mod BCG assembly vs a stock assembly on CO2. The stock nozzle broke within 300 CO2 rounds ( broke in half, the front section of the nozzle got stuck in part #117 and had to use pliers and quite a bit of force to remove it ), the modified setup still runs perfectly.

 

I'll try to post some pictures of it the following days to demonstrate exactly what i've made.

 

My nozzles broke using CO2. I think my old V1 M4 combined with one of the very first CO2 kits to hit Evike has a lot of little issues that have been ironed out in newer guns.

 

Here's a stock part #117 turned inside out; maybe we can see what it's supposed to look like after modding?

IMG_20100528_154313-1.jpg

 

Playing with the parts at my desk, I see what you mean about the added friction as the nozzle "pops" into #117 but I figured that was necessary to hold the BB in place and create a good seal. I'm guessing it gets worse when the part is held fast in the barrel.

 

 

I picked up a spare TSC nozzle even though mine is fine apart from a shredded large O-ring (probably need to clean up the gas hole in the brass tube); they now sport a black finish (teflon?):

IMG_20100528_160032.jpg

 

 

I know their stuff doesn't always work, but the "current stabilizing steel nozzle" is GTG.

 

One more thing; are these RA-TECH inner barrels any different or better than the "chormed" ones ASB sells?

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