Tanio Koba / KJW M4 GBBR Basic Information and FAQ

[daishi]

Huh, no idea. Mine has worked fine.

[grantmac]

Running the stock valve with cradle o-rings here as well and getting excellent consistency.

-Grant

[audi_bhoy]

Well i shall give it another try then! Just to make sure, you guys did put the oring in front of the cradle spacers and not ar its original emplacement right?

Grant, updates on rhop?

[grantmac]

Stock o-ring on top of the cradle spacers. Have plans to try something else for the valve which may work even better but that is yet to see.

Still waiting on tubing. Should have it within the week.

-Grant

[audi_bhoy]

Got a new scope earlier this week, changed the silencer to a QD type as well!

[grantmac]

Basic IR-hop complete. Still need some tuning since it's over-hopping .36g

Required substantial modification of the barrel cut-out since the KJW barrel is pretty shallow stock. Looks like there is enough room to do an extended (2mm) cut as well without sacrificing any airseal.
Smoothing the nub on the inside of the bucking was also a pain and I may have removed a little bit of the airseal section. Doesn't seem to affect FPS or feeding. I may modify the nozzle a little to place the BB slightly further into the hop-up.

I used the 6mm ID 9mm OD material for this mod, I've got some 6mm ID 8mm OD arriving soon and realistically that is the stuff to go for.

I've got another plan to experiment with once I get the smaller tubing. I may also sell the tubing in smaller sections since McMaster Carr won't ship to Canada anymore.

-Grant

[audi_bhoy]

You habe been able to source out the same / similar material?

I'd be interessed to know what it is, otherwise I'd need 2-3 kits of HS armory


And do you have the provided tools to smoothen the rubber? My friend has them, can't wait to mod it!

[grantmac]

The correct material is from McMaster Carr, it's semi-soft silicone tubing 6mm IDx8mm OD. Unfortunately they won't ship to Canada so I have to have it sent stateside and then shipped. If you want a piece I could send you some.

That size really doesn't require any sanding or other work. It does require you to cut the sides at the right angle and depth which takes some practice. I used a double edged razor blade which is extremely sharp, cuts it like butter. You can literally shave the material with it.
As far as I can tell nobody else has tried this tool for cutting it, I wouldn't use anything.

-Grant

[redzaku]

my hop up lever, part number 6(?) of the manual, decided to break
it sheared off the nubs that connects it to the "locking lugs"
also my threads on the upper receiver may or not be screwed by my Big Dragon NSR style key mod rail mount, is there any upper receiver that is compatible for the KJW? or am i SOL for uppers?
thanks all

[grantmac]

You can get both of those parts directly from KJW. They are excellent to deal with.

-Grant

[audi_bhoy]

Got bored, decided to add some stuff to the DMR...

Had a spring bipod laying around, but instead of mounting it on an adapter to fit a rail, I mounted it directly to the Viking 13" Handguard, solid and slim.

[DuCKy!]

Hi all, just got my hands on a second hand KJW V1 M4.
My first GBB; been using AEG's previously. Damn GBB is so much more fun.

I have a few questions:
1. The fill valve on one of my magazines doesn't have the little o-ring/rubber seal in it anymore. I think it still fills fine but not as properly/easily as my other mag. Is there something I can do?

2. I took my gun apart, cleaned and lubed according to one of the GBB maintenance posts on the forum. Used Super Lube (with PTFE) and it works like a charm. Super sweet and snappy shots. However, I noticed that the piston has some dents/scores on the surface. The piston seal looks to be aftermarket (Falcon - purple) and one side of the seal is slightly squashed. What has happened here? Should I purchase the Cradle X-Piston?

3. Apart from cleaning and lubing the gun as I've done, it's just a matter of adding some silicone oil into the propane adaptor and then filling up my mags correct? No other things need done?

4. Say for instance I decide to not shoot the full 32 rounds in my mag, what should I do to clear out the bullet in the barrel? With the AEG I just take my mag out, fire a couple of shots to clear the barrel then put the gun on Safe.

5. If I were to buy the Cradle XPiston, I'd want to get the Velocity Reducer too. Is it also worthwhile to buy the Polybelt? What about the Loading Nozzle Parts Kit?

Thanks guys!

[Comeau-SCS]

1- You can just buy a bunch of little o-rings it is very inexpensive and yes, sometimes they just fall off.
2- It would be better with a picture. Anyway check that the piston is tighten well too.
3- Always do a visual inspection and check that nothing is unusually loose or has a lot of wear
4- You could use a unjamming rod
5-If you dont have a reducer of any sort the airsoft is likely yo shoot too hot to be gamable. Polybelts and loading nozzle are mostly to have replacement parts.

[daishi]

ugh why in the WORLD would you get a version 1?

Contact KJW immediately and order a version two bolt and buffer assembly. With shipping should be like 50-60 bucks?

Then dont bother buying the cradle velocity reducer, just use some normal orings slip em on the valve and hold them in place with the rubber oring that was on your valve to begin with.

Bam, you've got a reliable kjw m4, without having to buy a nozzle, and belts and a reducer.

[grantmac]

I'll gladly buy anyones Ver.1 bolt group for $10+shipping.

I run a Ver.2 but there are aspects of the Ver.1 which I also like and KJW no longer supports them with parts so it's all cannibalism.

-Grant