KJW M4

[GismoBE]

Hmmpf, my digicam got stolen yesterday..

[weekenny]

 

How to for the valve.

 

http://shop.ehobbyasia.com/ra-tech-n-p-a-s-valve-for-kjw-m4-gbb-series.html

 

Pic of the valve, installs in a similar way to the cradle one.

[weekenny]

hmm wonder how good their hop rubber is

[GismoBE]

In the movie he's opening te valve with the tool, i'm trying to do that too.. Doesn't work.

I hope i haven't got a lemon here....

[GismoBE]

Allrighty, thanks everybody!

The video helped big time. It was a little different but it gave me the inspiration.

 

I'll try to make a video for other people in a few days-weeks.

[DesertFox]

For those of you with hop up issues, I just requested kjw to replace my parts #16 and #94. The new parts I receive allows the hop up dial to be seated lower therefore engages the hop up more. Before my hop up did not sound like it was engage for the first 4 settings and even at the highest setting, but now it clicks at every setting. I will be testing to see if my hop up will be improved.

 

My earlier tests involve completely taking out part #94 and using a single washer. Hop up greatly improved but since #94 was missing, the washer does not secure the hop up dial as well without the spacer resulting in shots hooking to the left and right, but this lead to me to believe my stock hop up unit does not sit low enough to engage up the hop up arm.

 

It seems like kjw has fixed the problem with part #94 allowing it situate the hop up dial lower therefore allowing to engage the hop up more.

Edited November 2, 2010 by DesertFox

[GismoBE]

Looks like I'm going to order that part too.

 

BUT: My M4 has got more range now that the npas is in. (345 FPS)

[PapayaSalad]

For those of you with hop up issues, I just requested kjw to replace my parts #16 and #94. The new parts I receive allows the hop up dial to be seated lower therefore engages the hop up more. Before my hop up did not sound like it was engage for the first 4 settings and even at the highest setting, but now it clicks at every setting. I will be testing to see if my hop up will be improved.

 

My earlier tests involve completely taking out part #94 and using a single washer. Hop up greatly improved but since #94 was missing, the washer does not secure the hop up dial as well without the spacer resulting in shots hooking to the left and right, but this lead to me to believe my stock hop up unit does not sit low enough to engage up the hop up arm.

 

It seems like kjw has fixed the problem with part #94 allowing it situate the hop up dial lower therefore allowing to engage the hop up more.

 

Not quite sure, but I guess there's no harm in trying. I'll order those parts too and see if it makes a difference.

[Kai_Wolf]

Sounds good DF! I will have to order those parts as well once it is confirmed that they make a good difference with the trajectory.

 

 

Any further word on those plastic uppers and their performance? Does it feel more like the older AEG plastics or like a POM or polymer material?

[DesertFox]

Quick hop up update: I did 1 test mag and it didn't seem like it was hoping enough, but I took down the gun and I realized I didn't screw in the hopup dial enough and it got loose as I turned it during my test. I'll try again tomorrow and report back.

[weekenny]

Sounds promising, I'll try to get the revised parts so I can remove the shrink wrap.

 

That said Claire doesn't reply to my emails

[GismoBE]

So it's normal that the range isn't that good?

And what to do about it, apart from the other part that's being tested by DF now.

[t_hum]

Some people have great range. Some people have poor range. The exact cause of why its so hit and miss is still being worked out by a lot of people on the board.

 

My gun has always had great range and accuracy. I have no idea what is different though even after lots of comparing my gun to several others. This latest insight about these parts may lead to a solution.

[Shadow_Ocelot]

Could you take pictures of the old and new parts next to each other, DF? The only reason I ask is because my hop has been all right on the higher settings, but ineffective on the lower four, like you posted. I'd like to see if they made any design fixes that are noticeable to the eye.

[GismoBE]

Allright thanks,

My range is kind of.. Poor..

But I only need it for CQB so that's kind of ok for now.

 

 

[PapayaSalad]

Sounds good DF! I will have to order those parts as well once it is confirmed that they make a good difference with the trajectory.

 

 

Any further word on those plastic uppers and their performance? Does it feel more like the older AEG plastics or like a POM or polymer material?

 

Definitely polymer. First time running the plastic upper through a game this Sunday. I'll post pics of any wear or anything afterwards.

[DesertFox]

Ok, short test showed that my Hop up works now I can see the bbs rising as I adjust it up. I'm sorry I can't really conduct more in depth tests, I live in a residential area and my backyard isn't very big.

 

The parts look identical to my old part, frankly I think part #16 is the exact same, but I ordered it for good measure anyways. The difference is in part #94, it's slightly different allowing part #16 to sit lower therefore engage the hop up more. I think this is better than the shrink wrap mod for the hop up arm since previously my first 4 settings didn't seem to engage the arm at all so even with a shrink wrap mod the hop up wouldnt even be engaged.

 

I originally tested this theory by removing #94 and using washers instead. I found that #94 consists of a lower half which is thicker and a skinnier top half which actually goes into the hop up dial. It's the top half that seats the hop up dial lower. So if you want to mod ur own #94 you would just have to shave or file down the top part.

 

using a single washer basically eliminated the top half of the spacer, and I was able to achieve massive overhop, but the spacer is actually required to stabilize the hop up dial otherwise there is side to side movement. So while I was getting great hop, it was somewhat erratic with shots hooking to the left and right.

 

So basically what I propose to t-hum is a modified part #94 with just the lower half, and then shims that fit into the hop up dial, allowing the user to adjust the height depending on the gun.

[t_hum]

I dont have my parts manual on hand right now. Can you take a pic of part 94?

[DesertFox]

My old part #94

 

Here is how the hop up dial (part #16) sits on top of it.

[t_hum]

I'd be interested to see the differences in size measured and compared to my stock #94. I can replicate this part easily if we can get some firm measurements

[weekenny]

Any chance of measuring your two part 94's??

[DesertFox]

Hmm, looking closely at the two part #94 they look identical. I'm looking at my part #16 the hop up dial, and my previous one is pretty fubared, probably due to my prior modifications with the washer.

[t_hum]

There must be some measurable difference if you are seeing some sort of improvement. Do you have calipers?

[weekenny]

Anyone else not get any reply at all from KJW for parts, or is it just me??

[DesertFox]

Ill try to borrow my friend's, but I get the feeling it may actually be part #16 now. That part is made out of plastic and is easily deformed or experience wear.

Edited November 3, 2010 by DesertFox