WETTI/AWSS - M4/SCAR/HK416 - Technical Summary Thread

[Exhopek]

Originally Posted by Eeyore

Part # 27 is broken on my WE SCAR. Is there anyone who sells a replacment part? If you followm the red arrow it looks like there was a bubble in the metal from a poor casting.

I guess this doesnt happen on the WE Scar. J/k mine had the same problem when and where did you buy yours? Are you using CO2 or green gas? Any mods or upgrades?

No one sells that part I have to get the seller to order from WE. I tried asking airsoft buddy they said they will order it but there was no reply from them yet.
Maybe if more people ask then they would keep it in stock.

[fumoffu]

Hey guys,

Not to sure if someone have a problem with the bomber light bolt carrier for the Scar.
I tend to clean the gun every match and sooo I took 5 shot and this happen.



Uploaded with ImageShack.us

[BoB]

Edit: there is a slight wobble between the recievers, but it was like then when I got it and it shot fine. There's also a propain stain above the selector switch. Is that normal?

Hi again. So my pdw is still giving me trouble.

With the mag loaded, I insert it and then cock the bolt back but it it will not go forward. It locks until I push the mag release button. The mag falls out and the bolt goes forward. I then re insert the mag , fire a round, and the bolt locks back again. Sometimes it will let me fire off a few rounds til it locks back. The odd time it smashes the bb into pieces. I thought it was an issue with the mag so I bought a new one and still the same problem. It seems like the mag isn't sitting correctly because if I hold the mag up into the gun, it sometimes will fire normally. It started happening when I took the top reciever off so it might be a fitment issue between the recievers but everything was put back together correctly. Could it be the hairline crack on the bolt carrier? Thanks in advance.

[ex]

Originally Posted by Strelok

Ouch, that looks nasty :x

I'm hoping to get a WE M4A1 in a trade soon. I'm totally new to the GBBR thing and i'll be honest, i'm kind of overwhelmed (or lazy, one of the two) with the sheer amount of info regarding them.

So the question is : Where do I start? What parts are to be replaced on a stock WE m4? I've heard they tend to eat through stock parts nice and nasty from time to time.

Thanks.

Originally Posted by juicy

+1, I'm wondering the same.

Replace part #66. Even though the new versions are reinforced I would trust an after market Steel version more.

and now from the WETTI master himself.

Originally Posted by m102404

Bonjour...what rifle do you have? SCAR or M4?

FIRST OFF: No rifle that stops working properly ever magically fixes itself. If something stops working normally...STOP using it. Fix the issue and then continue.

Second: There are a couple of known things with these GBBRs. Such as:
- you much cock the action before moving the selector (cock action, put on safe, load mag, cock action to chamber round...that's a nice safe way to do things)...if you don't and force it you'll break something

- if you have a jam...you can't just keep shooting to try and clear it.
--the steel nozzle will chop/smash bbs and then they'll for sure not go down the barrel...and you'll just be slamming your bolt into the nozzle that won't be able to go all the way forward...not a good thing.
--you CAN try to clear a single/double jam with a mag with JUST gas. It may blow out the jam.
--you're best off to clear the jam with an...SHOCK...unjamming rod (aka cleaning rod). The stock plastic ones are not still enough...get a real .22cal/.243 (6mm) cal rod.
--check the nozzle if you find bb fragments...I've had a piece of a chopped bb lodged inside the throat of the nozzle.

-If you have an M4 and it starts to act up...check to see that the white UHMW spacer hasn't ridden forward and is catching the hammer. It should be all the way back. I put a grub screw in mine to wedge it in place and it hasn't been an issue at all.

Parts to stock up on:
1. Hopup rubber - chopped bbs will tear the nubs off the stock hopup rubber. Nice to have that $3 piece on hand if you need it.
2. Part#66 - the CNC Tool Steel version is very nice. The stock ones are knows to wear out with use. (Warstore guys use/make them...they're shooting/gaming with the M4's a lot and have been wearing them out).
3. Nozzles - although the stock stainless steel one can take an enormous amount of abuse...having a backup one is nice (mine came with two).
4. If you have the "old" M4...switch over to the "CO2 upgrade kit"...which is essentially just the SCAR nozzle/chamber. It looks like that's the nozzle they're going to standardize on. It works, I've swapped mine over.
5. If you have a SCAR...the hinge plate.
6. Fill valves for the mags (MadBull replacement fill valves fit...at least they did for mine...and they're rated to CO2).

As you can see...the above list is pretty thin. More often than not these rifles are workhorses.

Tys

Originally Posted by m102404

Here's a quick summary of what I do to WE M4 rifles to give them a good once over. These are notes of what I did to take a clear lower WE M4 and prep it with a metal body. Takes about 2 hrs.

Notes:
- strip down every part and inspected
- scrub the bore... .243cal flat tip jag with a 6mm cloth patch. Grenade silicone oil works well
- rethreaded the upper...very minor and may not be necessary, basically taking the paint off of the threads
- add steel cnc part #66

Swap over to metal lower from clear lower - Takes approx 20-30min
-- Front Pin - pull out front pin, use small allen key to depress plunger through hole in pin. Pull front pin out the rest of the way. Caution, the plunger and spring will shoot out.
-- Stock - loosen castle nut all the way, back the receiver plate away from body. Rotate CCW to remove stock pipe from lower receiver. After 1 turn, remove the rear pin retaining spring and set it aside...it'll get it out of the way so the plate doesn't hit it as it goes around. CAUTION, don't drop the plunger out and loose it. Reverse instructions to reinstall...screw the pipe in so that it's just flush with the inside of the receiver. Too far and you'll block the bolt and the receiver won't close. Loctite is NOT necessary.
-- Remove Bolt Catch - punch out the retaining pin...most are inserted from rear to front, one end of the pin is serrated. Remove bolt catch spring, catch and spring and set it aside. Remove the bolt catch before you remove the mag release...and reinstall after you reinstall the mag release.
-- Mag Release - goes in like a real one...insert main piece on left side, flip it over place the spring and start screwing on the button. Depress button as much as you can and rotate the main piece (CW) to screw it on. If the bolt release is on the body, the catch will hit it as it goes around...better to have the bolt catch out of the way.

Removing the trigger assembly
- the trigger assembly comes out in 1 piece.
1. Remove the grip...careful not to loose the plunger and spring captured in the side of the grip. This plunger pins the selector in the body.
2. Unscrew the screw at the rear of the assembly that holds it to the lower receiver. This screw is just under the rear body pin.
3. Punch out the cross pin closest to the magwell...this would be the hammer cross pin on a real rifle. On most that I've seen, the pin is inserted from the left to the right side of the rifle. One end is serrated.
4. Cock the hammer set selector on semi
5. Remove the selector...pushes out to the left. You will need to push down on the hammer to "cock it further" and manipulate the full auto sear (tip it back and forth) as you rotate/pull the extractor out. You may need to over rotate the selector as there are a bunch of slots/cuts in it that match up to the sear arms, etc...
6. Lift the trigger mech straight up and out of the lower. CAUTION, on the right side of the housing, part #66 is just loose on the side and so is its actuating spring. The spring WILL fly off if you don't hold it in place with you thumb/finger. As soon as you get the housing clear of the receiver...take that spring out and set it aside...I've got at least two of these springs lost in my workshop somewhere

* replace part66 or the knocker or do whatever....
NOTE: If you're replacing the knocker (don't think that you need to), it is infinitely easier to do so if you first take part66 out first.

Reinstall trigger group.
- reverse the above
- Note: When putting the selector back in the full auto sear has to be in the correct orientation. The long down arm of it should be on the left and pointing down into the trigger group...the short paddle arm should be up and to the right. The long arm of the spring will simply push back against the housing...spring tension will want to keep the top of the sear plate pushing towards the rear of the receiver.


That should complete a lower receiver swap out of the M4.

Originally Posted by m102404

Hopup Mod

The stock hopup is so-so out of the box. Here are some things to consider. Shoot it first though...you might not need to do this.

You need to take the delta ring off and remove the outer barrel to pull the barrel/chamber assembly out of the upper receiver.

1. Green vs. Black
- original hopup rubbers are lime green...soft and the nub is a split tickler. They work well, but are prone to being nicked
- "new" hopup rubbers have a beautifully shaped concave rubber nub. They are smoke black in colour. Bummer is that the nub is a bit big for the hole in the barrel...and may protrude way too much into some barrels.

2. Hopup mechanism
- the hopup is simply a small ball bearing that pushes the nub down into the barrel to form a hopup bump
- the ball bearing is pushed down by a cone shaped collar
- the collar is pushed forward (applying more hop) by a serrated black, threaded collar that screws onto the chamber assembly. As the black collar is unscrewed, the grey cone collar is pushed forward, the metal ball bearing is push down = more hopup. The collars are pushed back by a spring.

3. The Hopup Mod
3a. remove hopup adjustment collars
-- push out the cross pin of the receiver stub mating ring (big black metal collar that goes over the chamber and holds it centered in the upper receiver). Put the spring aside.
-- gently pull the grey cone collar forward off the chamber. CAUTION, the little BB will drop out!!
3b. Remove the inner barrel
- push out the cross pin that holds the inner barrel to the chamber
- pull/twist the barrel gently out of the chamber
- pick/squeeze/flick the hopup rubber off of the inner barrel
** this is a great time to give the inner a good scrub!
3c. Mod hopup rubber
- turn the hopup rubber ring inside out
- put it on something firm...I use the inner barrel and slide the rubber onto the muzzle end of it
- shave (really, really sharp exacto) and sand (400grit wet/dry) the bump of the rubber evenly...until it is pretty much gone (a little bit of a bump left is ok, but I usually do until it's almost all gone)...obviously since this is the part that's going to touch your BBs...you want as even a finish as possible.
- flip it back right side in and put it back over the inner barrel...note, you want to line what remains of the bump back centered over the hole in the barrel.
- find some silicone wire shielding that is the right diamter to fit into the hopup bb hole...some undersized hopup nubs might work, but are usually too big.
- shave a 0.5-1mm slice (SHARP exacto) and put it into the hole...you want an nice even disc/doughnut so cut cleanly.
- then replace the BB, the grey cone collar and set the hopup all the way off.
- you should have just the tiniest bit of protrusion into the barrel at this point...if you don't have anything, you'll need a thicker slice...if you have too much, you'll need a thinner one. I've heard that guys will use a little disc(s) of paper to give it a bit more hop adjustment...but I prefer just to recut a slice.
- once you're happy with it...reverse the procedure to put it back together.

** NOTE **
This is a fiddly procedure. TANK, WILDCARD, Brian M and a few others of the WW group should NOT undertake doing this themselves. You'll end up frustrated...then I'll end up with a "rifle in a baggie" to fix.

Set the hopup with just the start of a bump. You'll need to run some rounds through it to bed it in. Apply more as you get out to the field to sight it in. These guns LOVE heavier BB's....0.30's work just awesome.

The silicone slice that you put in should apply a nice even force to the rubber, instead of there being a hard metal ball behind the rubber when applying hopup to your BB. I'm going to experiment with some other adjusters...but this setup has resulted in some wickedly consistent shot patterns so far.

[quote=m102404;1231456]The nozzle base is blue loctited onto the rod (ground it down a bit because it was too long). The nozzle body is blue loctited onto the base.

Originally Posted by m102404

I do not loctite the following (but you'll want to check these periodically):
- grip screw
- float valve FPS adjustment screw (maybe a bit of loctite if the adjustement loosens up)
- the screw that holds the bolt guide with the brass bearing onto the bolt
- screw that holds the trigger mech to the lower...just under the rear retaining pin
- buffer assembly retaining pin housing...it threads into the lower just in front of the buffer and holds the spring loaded plunger. It doesn't happen often, but I've had mine rotate out a bit once. Just check now and then that it's fully screwed down and hasn't backed out from recoil

Loctite (just a little, not gobs of it)
- any sling studs, optic mounts, BUIS iron sight attachment screws
- stock screws/nuts (like the little nut that goes on the end of the M4 LE/MIL spring plunger)
* the recoil of these GBBRs will eventually shake loose anything that isn't loctited down.

Grease/oil
- super lube (PTFE based) or silicone cylinder grease
- any bearing/pivot/sliding contact parts
- piston cup of nozzle/piston assembly - grenade silicone oil works nice
- grease on the bolt guide brass bearing
- grease on the buffer spring, buffer
- light oil on the nozzle oring seals

These things shoot really well with "oily gas" in the mags.
- either pre-oil the entire tank (need Carl's dohicky for that) or
- 1 drop on fill valve, quick shot of gas, 1 drop on fill valve, quick shot of gas, 1 drop of fill valve, fill the remainder.
- from empty a mag usually takes about 14sec to completely fill.
- the first shot of a very full mag is usually hotter than the rest...dump a shot or three before chrony.
- oily gas will lube everything in the rifle...including the hopup rubber ...
* I don't bother to do anything at the beginning, just top off the mags with gas and load BBs, then don't do anything special for the rest of the day of shooting...then when I'm done I run an oily mag through the rifle and store the mags with "oily gas".

Mag maintenance
1. Leave them filled/partially filled with oily gas. The seals in the mag love it.
2. The fill valves kind of suck...I've replaced mine with Madbull Stainless Steel grenade fill valves.
3. the back seal can be rejuvenated with a slathering of silicone grease if it's leaking (take apart..."massage" it with grease and reinstall)
4. when tightening the back plate...snug up the top and bottom screws first...then snug up the middle ones a bit less. Then tighten the top and bottom...then firm snug up the middle ones. Give it a touch of gas and listen for leaks...tighten the top/bottom. If you overtighten the middle ones you might flatten the back plate, creating more of a leak....just firmly snug for those.

[-Trooper-]

Does anyone know if the Stinger Hop Up for the M4 series will work for the PDW?

Edit: msged RA-Tech, and they said that it's compatible.

[technosnob]

Just a heads up for WE operators.

I found a local source for the nozzle o-ring (part #45). I personally haven't one fail but I like to keep extras handy just in case!!! The only snag is they require a minimum purchase of $25.00. I just bought a metric o-ring set which included 20 of them as well 29 other sizes for $23.00

http://www.globalrubber.com/

The o-ring size is 7mm ID with a cross section of 1.5mm (7mm x 1.5mm)

[coach]

reason why I like the new ultra slick multipurpose grease is because you can lay on a really thin layer and it's effective for a long time. won't dry up or become gummy. a thicker layer in areas you want more works too because it'll stay put and doesn't get flung off with every shot.

I think it was Renegade) that told me the Ultra Slick is now what use to be Super Lube or it's a suitable alternative.

[Qlong]

I'm doing a build with a RS upper, I've had Element, Allwin, and G&P MK18 RIS, and they all do not fit the RS or WE without mods to the barrel nut.

http://www.airsoftcanada.com/showthread.php?t=110862

Originally Posted by caboose36

Well I got everything working smoothly. I replaced the O-rings on the Valve.. Some silicon oil, and everything works nice now.. But on the other hand.. How much play should the Bolt carrier have side to side in the upper? I am beginning to get the pesky AR rattle from.. The bolt it seems.. Anyone else seem to be getting said problem?

Which way is your bolt moving? Side to side or parallel to the length of the gun?

[m102404]

Originally Posted by Armyissue

really man, a 43+ page tech manual about a toy gun just screams don't buy it.

LOL...so you're off of AEG's and GBB pistols too? I think there's a couple of entire forums filled with troubleshooting those....HAHAHA

But...point well taken. Time to thin this thread down.

******* NOTICE ********

I am going to review the entire thread. I will consolidate all the technical points made here and there throughout the thread and then ask a mod to delete all the others to trim this down.

Many an active thread becomes less than useful after a while because threre is just too much to read through...and that doesn't help someone hitting this thread for the first time to actually find what they want.

For anyone considering posting to this thread....there is the full expectation that you have read through the entire thread, considered the info here and how it may relate to your question. After an honest effort at that if you still have not found any clear/conscise points that address it, by all means post up.

If you have specific information that improves the information here (accuracy/content/updates)...please continue to generously provide that info and I will do my best to consolidate it.

If you don't take the time/effort to review all the info from others that has been graciously offered...then do not expect help in return. If I can, I'd simply have such a post flagged and deleted.

And....this isn't a shopping thread of where to buy stuff (there might be links though)...this isn't a "I want that"..."I'm selling an extra of this". Take it to Personal Messages or the Classifieds.

************************

[m102404]

Add on External Parts - Summary of what fits and what doesn't

*** this is not all my own info...this has been consolidated from numerous posts throughout this thread***

General
In general, real steel (RS) grips, stocks, handguards and externals fit the WE M4 series. I would tend to think that the RS grips fit the SCAR as well.
- RS trigger guards, grips, stocks fit the we gbbr's
- QLong is full of WIN
I'm doing a build with a RS upper, I've had Element, Allwin, and G&P MK18 RIS, and they all do not fit the RS or WE without mods to the barrel nut.

http://www.airsoftcanada.com/showthread.php?t=110862

Grips
- Also purchased a WA Pistol Grip -- which seems to fit fine on my WE M16 except I'll need to drill a hole to accommodate the fire selector pin/spring.

Trigger Guards
- what type of magpul enhanced trigger guard can fit on a we gbbr m4?
A - Real Steel or GBBR specific

Stocks
- G&P crane stock on their we? - yes, fit was good
- Magpul CTR fit fine...just a little bit of play

Stock Tubes
- If you get a RS stock, make sure that it's mil-spec
- UBR Stock tube
Actually now that I think about it did you have a problem with your rubber getting stuck in the buffer tube for the UBR? like I can push it all the way down.. not a big deal because it will stay in there but i find that with my LE stock it just slides out. My UBR its a bit of a tight fight and I have to use a hooked coathanger to pull it out. Just wondering if this is common.
So cut off the rubber and save it. If you want to go back to your original stock then just put the small piece in first, big piece in second, spring in third.......

Q - how far to seat the stock tube into the receiver
A - Turn until the buffer tube stops at the retainer pin (the small pin on the spring, which is vertical), then back it off until the buffer is aligned, and then tighten the nut


Handguards (threading primarily)
WE threading is "real threading"...i.e. G&P/PTW compatible and "the other" type when compared to TM compatible AEGs. However...the WE threads are inconsistent receiver to receiver. On some they are not very far off from being "TM compatible"...where all that is required is to take the finish. On others more material must be removed. A receiver threading tool such as the Madbull Delta Ring tool is handy...but a thread file can also be used. A "regular" fine triangular file can be used to...but you must take care to chase the threads evenly. If you're doing the work with a file...go slow and check often.
- SOCOM/Madbull handguards - MK18 fits
The threads were slightly off but not in a way to damage either the upper or RIS retainer nut (it was sloppy if anything). Just pay extra attention when you are threading it on to avoid cross threading it. You may also consider putting a couple rounds of teflon tape on the upper to take out the initial play in the threads.
- I used a PTW delta ring/nut on my WE M4 and it fit just fine

Launchers
In general...no compatibility issues
- Madbull X-series (will fit...move forward so recoil with support hand does not trigger accidentally)
- G&P 203 will fit

Anti-Rotation Pins
One of the "pins" that is captured by the AntiRotational pin sets is "fake" on the WE...so they don't really do what they would on a real rifle or WA style setup
- The anti rotational pins don't really do anything in airsoft except making your gun look more "cool". There is one advantage though, if you take your gun apart a lot, the anti rotational pins help with reducing wear on your lower where the stock pin fits.

[m102404]

Maintenance Summary

****the folllowing information is not solely my own...it comes from consolidating numerous posts throughout this thread****

In general most maintenance comes from Inspection and Cleaning/Lubrication. You must inspect for wear & tear on contact points. You must lubricate the magazines and working internals of the rifle. This is not a "fire and forget" system.

Look for broken parts, loose fit, excessing wear/cracking on all parts. Once you get a handle on where to look it doesn't take long to give it a once over before and after use.
Inspect:
- screws should be snug
- pins should be snug and set in far enough
- contact surfaces for scoring, marring, cracks
- nozzle for bent/crushed stanchions
- o-rings for nicks/tears
- inner barrel for jams/scratches/etc...


Lubricate:
- gas in mags...use 3-5 drops of thicker silicone oil in each mag and fill with propane. This will keep the mags sealed for storage.
- o-rings...use either thicker silicone oil or very light rubber friendly grease
- bearing/rolling surfaces...use light grease
- The criteria are:
- won't dry out
- will stay where placed
- won't slow down the action unnecessarily
- if it's contacting rubber...it's got to be safe for it (no petroleum products or products with a petroleum carrier)

There's an enormous amount of gas going through the system...and it'll dry out the o-ring seals quickly. They'll dry, get sticky/tacky and that'll slow things up.




Bolt Catch
- locking too frequently - stretch the bolt catch spring
- Not sure it has already been posted here or if you have already tried this, but there is a mod posted on Arnies about adding a regular AEG shim behind the bolt catch which supposely makes it run flawlessly and catch most of the time as the bolt catch stays straight when the bolt catch plate pushes it up and it catches the bolt with a larger surface than before.

Add shim between the bolt catch and the receiver.

- With no bb's in the magazine, you should have a little notch raised from the magazines, and with BB's loaded, the notch will lower. There is a switch on the topside of the magazine which enables and disables the lockback feature on each magazine.

Sealing Gas Mags
- gasket seal
- lube
- grease
- while we are on the subject of mags, iv been messing with mine trying to get rid of leaks. lithium grease is working great for me, got 2 mags up and running yesterday that would not hold gas before, but i noticed something. it seems like the ability of a mag to hold gas is closely related to the match between the mag body and the back plate. i would grease up the seal, install the backplate and get everything locked down- and the mag would leak, usually at the top or bottom. re-try with a different back plate, same seal and body, and get a perfect seal- no leaks at all. i should also note that all my mags have over-fill type valves on them, so no leaks is pretty impressive i think. to figure out if the back plate is a good match for a shell, put it on the back with no rubber seal in between. the top and bottom edges should sit really flush with the mag body, like right in there. most of the big leaks on my mags were coming from the top and/or bottom of the back plate so i think this is a key area for leakage.
as a side note, has anyone tried re-threading the female threads in the magazine? im talking about the ones that hold the back plate on. i stripped one while tightening the back plate screws damn zinc

i recently received a replacement part #59 (knocker cover) from renegadecow on arnies. it is a home made knocker cover made from steel. its really nice and dropped in perfectly. it doesnt have the sharp internal corners that the stock part has (just a hole for the knocker nub to poke through) so i dont see it breaking any time soon. if anyone needs a new #59 i would highly recommend this part. only cost $15 shipped from the Philippines. i can post up pics if anyone is curious.


Lubricating (Mags)
- three drops of Grenade oil or 5 drops of gbb oil in each mag each
- Also I'm finding I'm having to lube the bolt/valve a lot as after a couple (5-10) mags the valve won't slide smoothly anymore. Is this normal?

Lubricating (other)
- reason why I like the new ultra slick multipurpose grease is because you can lay on a really thin layer and it's effective for a long time. won't dry up or become gummy. a thicker layer in areas you want more works too because it'll stay put and doesn't get flung off with every shot.

I think it was Renegade) that told me the Ultra Slick is now what use to be Super Lube or it's a suitable alternative

Hopup
- Does anyone know if the Stinger Hop Up for the M4 series will work for the PDW?

Edit: msged RA-Tech, and they said that it's compatible.

Cleaning
- Shelledpants is full of WIN with this awesome pictoral cleaning guide
Hey gang,

I just posted up a cleaning guide. Please inform me of any corrections.

http://www.airsoftcanada.com/showthr...50#post1234750

- clean the sh*t out of the upper receiver, including the track the charging handle rides in, and the inner wall of the bolt. had the same problem when i replaced the charging handle. i mean go to town, brushes and stuff. it cant be too clean. then re-assemble and re-lube.

Jams
- The "Jamming" can also be caused by the swelling of the large O-ring on the black plastic nozzle assembly guide. I have solved this by pretty much working it in and racking the rifle about 300 times.

O-rings
- (this where to get it is worth posting up....thanks!)
I found a local source for the nozzle o-ring (part #45). I personally haven't one fail but I like to keep extras handy just in case!!! The only snag is they require a minimum purchase of $25.00. I just bought a metric o-ring set which included 20 of them as well 29 other sizes for $23.00

http://www.globalrubber.com/

The o-ring size is 7mm ID with a cross section of 1.5mm (7mm x 1.5mm)

Buffer Stop
- I would take a look at parts 123,124,and 125 (these parts make up the assembly retaining all the parts in the buffer tube when gun is open) to see if they set at the right height. I had these parts back out a bit causing all kinds of grief!!! These parts ride in the groove in lower half of the bolt. If not set correctly they effectively pinch the bolt between the upper and buffer tube. It maybe the issue since you just swapped out the lower.

Check to see if there is some wear on the pin(125) and the groove on the underside of the bolt.
- i take the buffer retainer out with a pair of scissors. yes, scissors. just spread the blades apart enough so the points fit in the slots on the top of the retainer. then turn like a normal screw!

[m102404]

Must Do's - Functional

***the following info is not solely my own....it is a consolidation of the numerous posts in this thread***

There are just a few MUST DO things with these rifles for reliable function.
1. Loctite (blue/temporary) everything you don't want shaken off of it.
2. Part #66 must be replaced with a steel unit (CNC or wire cut)
3. On older models the Forward Assist button must be epoxy/super glued on or it'll shake loose and pop right off
4. Lubricate
5. Regular inspection


Steel Internals
- hammer/sear/etc...

Replacement Internals
- Part #66
just becareful when tearing down and reasembling the trigger pack the spring for part 66 (PART67) likes to shoot in random directions and get lost

Plastic-to-metal lower receiver swap
- I had a similar body issue with mine. I had to file the holes to get them to accept the pins for both the front and rear pins. The only issue I have (which is small and not a problem for me) is that I need to partially rack the bolt to get the rear of the upper to mate properly with the lower. As soon as this happens it's smooth sailing again, as the pin goes straight in without an issue.
- Ok, so after filing away for about 30 minutes with a round bastard file (carefully, but still making progress), I got the fitment down. Now it's about as rattle-y as I recall Chris and Rub's being.

The issue with non-firing, was an unrelated one, the white spacer on my bolt had moved forward -somehow- over the last month or two of non-use. Put it back in place and the gun fires a treat.

ULTIMATELY what I did, was file the front pin on the upper down slightly the allow play between the receivers, and then filed the rear to allow alignment of the pin.
- I had to ream out the tab and burnish it .. now it fits but is tight.. and has to be tapped in and out ( but is getting looser with use) I have had zero function issues thankfully


SCAR Specific
- The fix I performed earlier managed to work for a few weeks and then I noticed the roller pin coming lose again. Tried further deforming the end of the pin with grooves on it in an attempt to get it to stop coming loose still when in place. This lasted another couple games until about 3/4 of the way through the FR Night game on July 3rd where at one point the gun jammed on me. After opening it up noticed the roller pin had once again found it's way down beneath the fire selector.

Fixed the problem this time by removing the trigger assembly and replacing the hammer/roller/roller pin combination with new parts. So far things seem to be solid.
- After deforming the end of the pin a little so it stays in the hammer assembly better I reinserted it. Reassembled and gun is shooting just fine again.

I made sure to not sit there and try firing my gun repeatedly while it was in this 'broken' condition. Thereby hopefully avoiding any unnecssary wear on any other parts. Just to play it safe though I ordered some extra internal bits and a replacement set for parts #50, #51 and #52 so when the time comes I can rebuild this thing.

Forward Assist Button (older versions)
- So, I use epox and glue the forward assist button, the forward assist body and the first 2 coil of the spring altogether and custom cut the spring a bit. It's working so far.


I'm interested to see how's that retaining screw and the bolt finished look like. Maybe I ask Lanny to show me next time.
- I cross drilled mine and put in a pin

[m102404]

Throuble Shooting

While there are plenty of posts relating to issues with the WE systems...in general they can be traced back to a small number of root causes. The good news is that there are resolutions for these issues.

Most jamming, venting, sticky operation issues can be traced back to inadequate lubrication. There are mechanical bearing parts...there are gas sealing contact points....they must remain lubricated.

When the "new" hopup (black vs. original green) came out there were quite a few reports of way too much hopup being applied...and some torn ones. The root issue is that the nub of the rubber stuck down too far into the barrel even at the lowest settings. You can either mod the hopup rubber to apply less hopup....or you can try other hopup rubbers (i.e. original green, Stinger)




Valve Freezing and Gas Venting
- NPAS valve freezing open

Too Much Hopup
- I Reccently gammed the M4 and noticed my hop up is realy finicky. If I move it a small turn the hop up is so strong its holding my nozzle in place and when I let it off I get shots flying left and right. I was using .25 bb basterds while shooting, my stock barrel/set up is the new Gen.2 hop-up system with 6.03mm inner barrel. I am also NOT comfortable perfoming the hop up mod myself as I dont trust myself to not srew it up
- I replaced both of my WETTI M4 uppers hop ups with the Stinger hop up. If you don't want to go this route you can take the hop up rubber off and trim down the integrated "nub" so that the adjustments are a little more tame.
- I'm not sure if it's me or what but twice now I've had my SCAR where after firing for some time the BB's start skyrocketing (too much hopup) so I turn my hopup off and they either continue to shoot at planes or it's like throwing a wiener down a hall in terms of accuracy. After a while of this bb's then get constantly jammed in the barrel. When I take it appart I find the hop up has ripped (now theres a flap). This is the second time this has happened. Are there any better hop ups for the SCAR out there.

Too Little Hopup


Safe/Semi/FullAuto Operation
- But one thing that is bothering me.. it there something wrong in the trigger box if I can move the selector switch from semi to safe when the hammer is uncocked? Is a problem with the sear? I only did it a couple of times to figure it out why but couldn't.
- Not sure if i'm crazy or something but is it strange to put the selector switch on safety when the charging handle is not pulled?
- The m4 has to be in Semi or Safe if your mating the upper and the lower. It can not be in Auto.
- Like the RS version you can not put it on safe unless the weapon is cocked.

[m102404]

Internal Modifications

NOTE: This is not solely my own information...it is a compilation of info from previous posts in this thread.

This section is about mods to the internal parts...either to improve durability, tweak performance or modify whatever. I'm not sure that anything in this section is simply a "lego-esque" snap in part and you're done. You've got to understand a bit of what's going on and check your specfic setup.

Adjustable FPS
The following items are ways to alter the nozzle setup to affect the FPS of the rifle. These mods are independant of simply switching gases...which will also affect the FPS of the rifle. Note...the adjustments with most of these to go from 400fps to 350fps are very, very fine...so use a chrony to confirm you FPS before hitting a game.

NPAS
Put simply...refer to RATech's NPAS system. The NP part refers to Negative Pressure...this is different from the WA system that works on a Positive Pressure system. If you want to understand how it works...check out Redwolf's site, they have a great pictoral explanation of "how a GBB works". They describe the action of pistols...but it's the same thing for these GBBRs.
* by far the most popular adjustment system
* works by setting the position of the float valve further forward or back in the nozzle body...further back = more velocity...further forward = less velocity
* well built...machined edges can be very sharp, there's no harm in breaking the edges very slightly (that roughly means take a file and ever so slightly hit all the right angles of the cut outs)
* simple system...sound design
* need adjustment tool...it's a very small allen head grub screw stuck in an L-shaped bar...you can definitely make your own, but until you do..don't lose it.
* need to remove the bolt assembly from the upper receiver to adjust...but that's not too hard
* generally stays adjusted where you set it...but a tiny/little bit of temporary loctite doesn't hurt
* does not come loctite'd together...which is good. But you MUST use temporary loctite for final assembly or else it'll come apart with use.

TCS
TCS was first to market with a consumer add on product that was reported to adjust the FPS. It consisted of a new piston body (usually blue anodized alum), a sqare sectioned threaded rod and a threaded collar to set the position of the nozzle (thus the FPS).
Good theory...didn't work well in practice due to either poor manufacturing, tolerances, or design. The main issue with some of them was that the grub screw in the threaded collar was so small and had so few threads holding it that it could not take many readjustments before it "wore out". Also...it was still necessary to loctite everything in place....so the "quick adjustments" of the system were no quicker than anything else.
* looks nice
* "fragile"/not durable

Mod the float valve
Ways of modding the stock nozzle assembly were the first "home brew" methods of adjusting the FPS. With any Red Green "fixes" like these...the devils in the details and execution. Here's a couple of ways to do it....some are dead simple...others take a bit of work.
1. Insert a spacer behind the float valve. Guys tried using a 6mm solid bushing (CA ones for whatever reason)...slipping it over the guide rod stub that sticks into the nozzle body. This would in essence push the float valve forward "permanently" to reduce the velocity. Some guys would try to epoxy or superglue it in place. The obvious issue with this mod is that it's a fixed setting and it can break loose.
2. Find a nut that fit the threaded portion of the rod that stuck into the nozzle body and use that to essentially have the same effect as the bushing mod above. Loctite or super glue in place. This was more secure...dependant on finding a propper fit...could come loose...fixed setup dependant on the thickness of the nut you find (or you could trial and error grind it)
3. Make a "nut" to fit the threaded rod. I machined mine out of brass and make the threads "tight" so that it'd stay in place. No issues with it coming off...but it's really a guestimate trial and error to get the FPS where you want it. Add in temp variables and it's basically like throwing darts in the dark.
4. "TSC Variation"....thread the stock rod more so it can run up further into the nozzle body (less FPS) or be backed out (more FPS). Place a nut on the threaded rod to jam the nozzle body in place where you set it. Still need to loctite it. Resulted in a fidgety setup that was mechanically more durable than the TCS version....but was still subject to it coming apart with heavy use.
5. "Make your own NPAS valve"...essentially put a screw into the stock float valve. It's simple to tap and thread a hole in the center of the stock float valve. It's also simple to use an appropriate machine screw....grind on a male hex pattern on the end, grind the head down flat to make a plate. It's a bit hard to find the small allen head grub screws....but if you can and have access to a lathe it's pretty simple to knock up an adjustment key. It works...it's solid...you've got to be attentive in making it. I made a couple....I'd rather buy the RAtech one
6. "Make your own float valve"...I machined several out of brass. Different sized inlet holes...different sized bore holes. It works...very easy on a lathe. It's very much a guessing game to get the FPS result you want. Non adjustable...unless you mod it further.
7. "Make your own complete nozzle assembly".... soon...soon

Nozzle Buffer
Behind the nozzle body, on the rod, sits a small white plastic collar. This collar is ESSENTIAL to the operation of the rifle since it determines the "in battery" position of the nozzle (like headspace in a real centerfire chamber). If it's not there, smushed, crushed...your nozzle will not seal completely and you get failure to function.
I've crushed some nozzles...and I think more than a couple others have too. I think that if you get some jams and you keep pounding away at it (e.g. jamming during a full auto string) that the nozzle basically stops at the plugged up section of the chamber and there's nothing stopping the big heavy bolt carrier from slamming forward...and the stanchions of the nozzle body take the worst of the impact.
So I used some dense rubber material that had just a bit of give to it and cut out a disk to go over the rod in place of the plastic spacer. The thickness is just a bit over the length of plastic spacer....so when the bolt carrier comes into battery it compresses the rubber to keep the nozzle sealed. I haven't had many jams...but I'm hoping when I do the rubber will take up at least some of the shock to the nozzle body and save it from crushing (at least if I switch on my brain and stop shooting after a jam).
The first one I made was a bit crude since I cut it out with a hobby knife...I figured I'd make a nicer one if this one wore out. It's still going strong....so I haven't made another. I figure that a sharp hollow punch sized to the same size as the nozzle base is the way to go.

Changing out nozzles/rod assemblies (Hints and tips)
- loctite and breaking loctite
-

Stop the centering collar from sliding around
- i can easily put my m4 selector to safe, uncocked. no firing issues related to same.
however, i did have a firing issue which was resolved. 'twas due to the plastic block
in the bolt that has moved forward a bit that interfered with the hammer. causing the
pin to hit the mag valve half press and bolt didn't reseat. try moving that plastic back all the way to the back. some even removed this. also, both receivers can be put back together with hammer cocked/uncocked. hope this helps.
- crazy glue
- pin it



Well I got everything working smoothly. I replaced the O-rings on the Valve.. Some silicon oil, and everything works nice now.. But on the other hand.. How much play should the Bolt carrier have side to side in the upper? I am beginning to get the pesky AR rattle from.. The bolt it seems.. Anyone else seem to be getting said problem?


Inner Barrels
- rubbers and inner barrels for the WETTI M4 Gen 3 are they the same as AEG or GBBR Specific?

[m102404]

Breakdowns/Failure Summary Reports

NOTE: The following info is not solely my own...it is a compilation of info from other previous posts to this thread.

- First day out with my brand new WE 416. 3 mags through it on semi auto and the metal lower receiver has a big crack right across the top near the buffer tube. That and it now jams every shot.
I plinked a couple mags through it at home after it got out of the box and it was fine.

- Hey guys,

Not to sure if someone have a problem with the bomber light bolt carrier for the Scar.
I tend to clean the gun every match and sooo I took 5 shot and this happen.



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