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

[MrEvolution]

Originally Posted by m102404

Sorry Sam...over-eager on purging posts...

Quick summary setup?
- SCAR/M4/PDW
- CO2 or propane
- RAtech's NPAS?
- other mods?

Are you in for Oct 3 FR?

Tys

WE CQBR
Propane
RATECH NPAS +part 66 and one other.
Genuine Magpul ASAP + BAD Lever (removed as it was disabling bolt catch)

Yes I will be there, im on tan :P

Originally Posted by m102404

T
Post game
- wipe down rifle (there's rusty steel bits on mine and it always seems to rain)

Thats because Leecas is always there

[SHaKaL]

I received my ratech kit. I have already installed the npas (didn't forget to put blue locktit)
Do i install part 66 and the other metal part or i wait until failure?

Other question... How do i install the new hopup? (and all its parts). my hopup is the one with the ball bearing.

I will run my we with propane.

[MrEvolution]

Originally Posted by SHaKaL

Do i install part 66 and the other metal part or i wait until failure?

I had it done all at once since the gun was apart. No harm in that.

[Thenooblord]

steel part 66 will damage a stock hammer just FYI

[m102404]

Originally Posted by Thenooblord

steel part 66 will damage a stock hammer just FYI

I have...and know several others who have...replaced that part and not worn out their hammers. Some of them have shot little...some a lot.

I get that a steel part rubbing against a different metal will wear it...but can you qualify/quantify your statement?

[m102404]

Sam,

Swap out the knocker (the other part) back to stock...leave in the NPAS valve and steel part #66.

1. make sure there aren't any burrs or catches on part 66...not to round off the edges or anything severe...but check to see it's not catching/digging into the hammer as it moves. It should also move completely smoothly up and down in it's slot.

2. Pull your bolt carrier out and put some thicker silicone oil (try either grenade oil or 60wt RC shock oil).
- put a generous dab on the 2 orings on the nozzle body
- put a little on the o-ring of the float valve..it must move back and forth freely.
(see edit)
- extend the shaft/rod and put some oil on the piston cup and on the spot where the rod goes into the piston head. Work the rod back and forth...it shouldn't bind/catch....it should be smooth.
- if it's still not moving smoothly...you might have to take the piston out of the bolt carrier and see if the end of the rod isn't too big for the black piston body. Lube there too.
- lube the top roller on the bolt carrier
- make sure you've got a bit of grease on your buffer spring and just a touch on the buffer where it'll rub the stock pipe...it should run in and out smoothly.

3. make sure the white spacer is all the way back (to the rear) on the piston body.

4. back the float valve almost all the way back (most FPS)...it'll shoot too hot but we're just testing now.

5. with an empty mag...
- hold down the knocker valve and put 2-3 drops of oil (same as above) right in the top seal of the mag. The knocker valve must move freely...so a little light lube there if you need it.
- at the bottom of the mag....put 2 drops on the fill valve...give it a quick shot of gas...put 2 more drops on the fill valve and then gas the mag up

....it'll be overlubed at this point...but ok for testing.

Rack the bolt...the bolt should be smooth and not stuck/sticky anywhere. Work it a bit to see that it's all free moving.

Fire (bbs or not) on semi...count 1 mississippi between shots for now. How many shots do you get off a full mag?

If it's working decently at this point...tune down the float valve to a sane velocity level....keep oiling the mags and test firing. If it's still consistent at this point...then start reducing the amount of oil in the mags. Pull the bolt now and then...it should have a nice even coating of lube pretty much everywhere. The lower internals should be lubed too.

If you get to the point where you think it's stable and the oil levels are just enough to keep it lubed...then you should be good to chrony. Remember to pass a AEG cleaning rod down the barrel to get extra oil out.

Other guys have noted that it often takes a fair bit of bolt racking to set the o-rings to the chamber so it doesn't hang up there.

******EDITS*******
- corrected masses of spelling mistakes...need more coffee
- * I also noticed the other day that the newest batch of RA tech springs were really stiff in comparison to the old ones

This increased resistance makes for the float valve slower/delayed in closing.

If you crap out on all of this, try swapping the stock float valve spring in to use with the RATech valve....you'll need to clip the little cross piece leg out of the spring...compare to the RAtech one and it'll be evident what to do.

[Dart]

Well it would seem I have discovered something new with the co2 mags. If your going to store them with a powerlet in... do not leave them on there side. The liquid co2 seems to flow into the valve and cause it to leak. I just had 2 randomly start leaking on me.

Makes me wonder if co2 is better stored with out the powerlet. The one sealed up again after a few shots the other one refuses to seal.

Edit: ok I found a solution to make the mags stop leaking. Seen as the seal on the co2 mags doesn't seem to be rubber so its not reacting to silicone like normal. I found that by stretching the cone spring out a bit it puts more pressure on the valve and seals it up.

On a side note can someone pull a GG valve to compare?

[m102404]

I've got a junker WE mag...won't get a chance to pull it apart until next week though

[Daiviet]

K, i've been working on fixing a buddy's 416... I've narrowed the problem down to the white spacer, its sitting in the middle of the bolt assembly. Now...

HOW THE HELL does this thing move? I've tried pulling it back with a lot of force, thing doesn't budge. How much force was required, or how much time did it take for you guys to move it back?

[m102404]

Lots...sometimes. It's a "stick-tion" fit. Surprising that something on so tight can actually move...but those are the forces these rifles move around with.

The exterior condition of it does not matter at all...so gripping it with big adjustable pliers doesn't matter.

I found that I could really move tight ones by twisting it as I move it...a little thin/light lube helps (clean it off after though).

Or...take the piston out of the carrier...brace the back of the piston body (black tube) on something softish (shop towel on a bench), use a monkey wrench to put on the top of the plastic spacer but not gripping the tube at all and then use a light touch with a hammer to nudge it down bit by bit.

Get it clean, dry...free of oils. The spacer and the tube. Then use a touch of saliva or water to lube it just a bit and put the spacer back on. Note that it usually goes on just a bit ahead of the actual base of the piston body when it's all snugged up in the bolt carrier. just before you get it into final position...use a drop or three of crazy glue (cyanoacrylic) to fix it in place. Super glue needs water to activate (thus the water/saliva)...depending on the setup time of the glue you can try to apply it so that you get as much as possible between the tube and the spacer to hold it in place. I think that Red/perm loctite would do it to...but if I used that I'd coat it well before putting it on...loctite sets up in the absence of air. Let sit to fully cure before shooting it.

OR

tap the side of the spacer when it's in position and pin it in place with a small set/grub screw. The screw can't/won't back out if you position it so it's trapped by the bolt carrier when the piston assembly is screwed back into the bolt carrier. (hope that makes sense). I did that to mine and it hasn't moved since. Won't be a mess to take apart if I have to like gluing would be.

Tys

[MrEvolution]

Thanks Tys.

Just another note before I attempt any of the remedies, when I rack the gun, sometimes the bolt 'sticks' half way and I have to really yank on it. Once the hammer is cocked though it is fine and i can do it easily after that. It seems to happen once and a while only.

[Dart]

Originally Posted by MrEvolution

Thanks Tys.

Just another note before I attempt any of the remedies, when I rack the gun, sometimes the bolt 'sticks' half way and I have to really yank on it. Once the hammer is cocked though it is fine and i can do it easily after that. It seems to happen once and a while only.

This is on a scar? because my scar does that too. It narrowed it down to either the Orings are getting "pinched" or its the BCG on the hammer just coming to an odd point. If I rack it quickly it never really has an issue.

[MrEvolution]

Mine is an M4

[El Cactus Loco]

does it only happen when you use the bolt catch, or when you let the bolt carrier snap forward? my bolt does the same thing (like its getting stuck half way back) like, its still easy to rack, but its weird.

[caboose36]

Got the Madbull fill valves for my mags. It seems the "faces" or tops of the fill valves are bigger then the originals. Do I drill out the beginning of the hole to make it bigger, or make the circumference of the fill valves face smaller with the dremel?