[Jugi]

Alright, I have few issues with my Tanaka M24. Here is a list of upgrades that it has internally:
- Palmer's 12g co2 rig
- KA vsr conversion
- Laylax 555mm barrel
- Nineball rubber
- Creation chamber
- G&G power pack (without the striker spring and the L-shaped arm)
- G&G valve knocker
- G&G gas route connector spring

So, my problems are what the title says: it only shoot ~400 fps on 0.2g bb's. The fps before the conversation to co2 was decent 525 fps on Begadi's power gas. I tried it with the G&G striker spring, but then this happened: the trigger sear started slipping, so the bolt wouldn't cock completely. When I pulled the trigger, it was bit stiffer and I only heard a small click, but the valve knocker didn't move at all.

After that I switched back the original striker spring and replaced the trigger sear with a KJW's one, and it started shooting again, only with low fps. It doesn't change the fps significanly if the pressure is 100 psi or 200 psi. Do you have any idea what could be wrong, because I'm a bit lost :shrug:

 

[Jugi]

A bit silent here...

So, I thought that a video might help a bit. The bb's in the video are 0,25g because I didn't have 0,2g:
http://www.youtube.com/watch?v=Q1-L9HTL2Cg&feature=plcp[/UR

The bolt has original striker spring inside, not the G&G. The weapon fired well (ignoring the low fps) until I tried the G&G striker spring again, and the trigger sear failed again as can be seen on the video. Should I get a new trigger sear machined from steel or what should I do?

And one more thing: the weapon shot few shots of ~560 fps after I cranked the psi from 150 to 200, then the fps went back to "normal". Can anyone figure out the reason for this?

 

[Wolfgeorge]

It's a problem with the sear.
Try to adjust the sear with the 3 screws on the trigger group.

If you still have problem you'll have to open the trigger group and check what's wrong.

Wolf

 

[Jugi]

Alright, thanks for the quick reply. I really hope that this problem would fix by adjusting those screws... Is it the C-screw that I should adjust or did I miss something?

I got the rifle to shoot a couple shots at 560 fps after I cranked up the psi from 150 to 200. After that it returned to that what can be seen on the video. Any ideas what would cause this? And should the G&G striker spring be such a hard one to install, because mine is a bit longer than the original and it scratches against the inside walls of the bolt when installing it.

 

[Wolfgeorge]

Well I had a similar problem like yours after I installed the G&G striker spring, I had to use too much force to fit it.
After the instalation was too hard to push in the last few mm of the bolt.
From that day I had the problems with the sear(valve knocker).

If you put a piece of coke can on the receiver over the bolt it will fix the problem but the bolt won't be so smooth.


Wolf

 

[Jugi]

Alright, a little update: got the trigger problem solved by making a little shim between the trigger and the metal piece that has two holes and is connected to the trigger's small spring.

All that is left is the problem with the low and inconsistent fps. Could the problem be in the regulator? Or is it the bolt, because the magazine is fine?

 

[Wolfgeorge]

Check a normal(Untapped) mag if you have.
The only that could go wrong with the bolt is the striker spring, or if there's a leak of gas between the bolt/mag connection, check the o-ring at the bottom of the bolt to see if it's worn.

Wolf

 

[Jugi]

I sure would, but I don't have an extra mag...

The striker spring is as it should be, only thing is that I don't know if it has lost a part of it's tension. The seal on the bottom of the bolt is fine, checked it today and I recently switched it to a new one.

There are couple things that I have in mind: is there supposed to be a circular piece of metal behind the pcs valve? I tried the gun without it, and it shot hotter without it, but the bolt got jammed after that. The second idea is that mine hop-up rubber has taken some damage to the "lips" that make the air seal. Could it be that it is leaking from there and causing the low fps and inconsistency?

 

[Wolfgeorge]

That should be it... The ripped seal rubber of the hop up. Try to fix that.


Wolf

 

[Jugi]

Tried it with a new hop-up bucking, didn't have any affect. But I managed to install the G&G striker spring, and it shoots a bit better now, about 425 fps with 0,25g bb. I think I will blow the magazine in pieces and check if there's something wrong... You guys have any ideas what is this all about?

 

[Wolfgeorge]

The fps are still pretty low... I've seen over 600fps on propane with the G&G striker spring.
Mine with greens fires at about 530 with the stock spring.

Check the valve knocker to see if it's worn.


Wolf

 

[Jugi]

Yes, I am aware of that. I think that this gun should be able to reach well over 600 fps... The valve knocker is okay, because it's about one week old G&G knocker. Any other ideas?

 

[Wolfgeorge]

Check the impact plate of the mags, maybe they are worn, also are they stock or G&G steel?

If everything is OK then it must be something wrong with the trigger or sear adjustment, I can't think of anything else right now.

There are not many things to go wrong with the bolt.


Wolf

 

[Jugi]

There isn't a impact plate because I have installed the power pack, if you are talking about the plate that valve knocker hits?

Can you tell me how the trigger adjustments can affect fps, because it really doesn't make any sense to me... I think I will check the valve in the magazine next to see if it is jammed or something.

 

[Wolfgeorge]

The screws on the trigger group adjust the valve knocker, you can mess with the screws and adjust the sear engagement.

I'm guessing that something happened there. The bolt problem of the video is fixed?


Wolf

 

[Jugi]

Okay, could you tell me what screws should I adjust at the trigger mech?

Yup, the problem with the bolt is fixed. Another problem came up though: when I cock the bolt, put it to safety and pull the trigger, I can hear a small click. After that when I put the safety off the gun fires itself. So what screws should I adjust at the trigger mech?

I still think that the reason to the low fps is inside the mag. When I disassembled it, I noticed that the valve looks a bit different compared to the picture in the long mag disassembly guide. Here is the picture:

Do you have any idea what this is all about?

EDIT: for some reason the picture doesn't show correctly. You have to click it with the right of the mouse and show picture or something...

 

[Wolfgeorge]

You need to adjust the C screw IIRC (check for the manual page I posted).

Basically there are not many thing that can go wrong in the mag.
The G&G power pack didn't work with my long mags! When I installed the power pack the outlet valve left open so I couldn't even fill with gas the mag. So all I did was to install only the piece that gets knocked by the sear.
I did a long search on this matter and had a long discussion with Brainplay on airsoftforum. It looks like the power pack has some quality issues, you can't install it in all guns....!

I really can't think of something else... Maybe there's something bend or broken in your gun. There's avideo on you tube about tanaka and KJW M700 trigger disassembly, there must be something wrong there. I'm on my mobile ATM and I can't provide you the link.

Also did you installed the power pack cocking piece on the bolt? If you did reinstall the stock one and check again.


Wolf

 

[Jugi]

I think I will have a look at the trigger mech once more, hopefully I can find something...

I had the exactly same problem when installing the powerpack. It fixed when I changed the L-shaped arm in the magazine to the original.

I have watched that video a few times, and the only differences were that I only had one spring instead of two that are in touch with the trigger itself. And that I now have the shim in there.

Yes, the cocking piece is installed too. I already tested it with the stock piece, and it was laaaazyyy... it shot about 30 fps, though I only fired it once because it felt a bit sticky when cocking the bolt.

 

[Jugi]

Alright, time for an update:

Got the gun fixed by changing the stock internals to the magazine. I was very pleased when I fired it for the first time and the chrono showed 626.6 fps with 0,25g bb's.

 

[Wolfgeorge]

What gas do you use? What was the fps of the second and third shot?


Wolf