WE Gas Blow Back M4A1 Carbine

[PaulB]

Another happy Airsoft123 customer, brilliant customer service.

[snorkelman]

When the way something's built causes it to malfunction, I call that a design fault.

 

Sure, except in this case it isnt really a malfunction its more of a a fail safe - the trigger only fails to release the hammer in auto if some other aspect of the system is already in an error state - be it bolt carrier group not fully forwards, hammer lock trip face worn so bolt carrier doesnt have any effect on it, alignment of BCG and hammer lock out of whack etc.

 

when airsoft guns replicate the fire control of the original this closely they're going to reflect same behaviour as the original when they hit those error conditions.

 

On the airsoft version they could have factored in a little more leeway and loosened up the tolerances to account for wear or alignment issues - trip face on the hammer lock extended so it sits higher, bolt carrier built up a little to strike the hammer lock earlier. Trouble is you then end up with the gas release valve on the mag starting to get triggered before the bolt carrier is fully home

 

[tangman]

For those who are interested, here are a few quick impressions on the TSC Uni Guide Rod.

 

Installation was tight, getting the whole assembly into the Valve Rod Stabliser required some force. I can't say how much tighter than the stock one though as a friend installed it for me

 

I'll add that there are no instructions, okay its not exactly rocket science but if you're not familiar with how it works or if you havent read up on any info then you can make some mistakes, me being one of those people.

 

Initially I had the adjusting nut BEHIND the nozzle assembly and not inside it until I checked the AS123 website and saw the pics of it installed

 

-

 

For easy reference, I'll refer to the "Locking Power Adjustment Knob" as "adjusting nut"

 

The locking screw on the adjusting nut, well what can I say, I've lost mine already. It was on tight enough so that you couldnt turn the adjusting nut but evidently not tight enough. At some point when I was testing/chronoing it, it must have worked itself loose and is forever gone into some kind of crevice.

 

So lesson learnt, make sure you tighten it was much as possible.

 

Here are the pics of it installed, I hope I've done it correctly, if I have not then someone please point me in the right direction

 

I deliberately left parts 42-46 off, so just imagine that they are installed

 

So if I'm not mistaken, the following picture shows the adjusting nut configured for the Maximum power setting (adjusting nut flush with part 41)?

 

 

And in this next picture, it should be at it's weakest power setting as the adjusting nut is sat as far away as possible from part 41?

 

 

-

 

I can't help but think there is still something amiss with it though, I chrono'd it earlier at what I think is the maximum power setting (adjusting nut flush with part 41) and was getting an average of around 340-345 FPS with Propane and Blaster 0.2g BB's.

 

The lower readings were around 325FPS and the higher ones around 365FPS, I chrono'd 2 mags consecutively and I would say about 85% of the readings were in the 340-345 range

 

Everything was done outside, the temperature was around 13-15 Degrees Celcius.

 

I should also add that I did not reinstall the Part 37 O Ring, it didn't seem to be of any use, could this be what's causing the low power? Everything else is installed like the stock parts from what I can see.

 

It seems low powered compared to the results rvp69 was getting (as posted here http://www.arniesairsoft.co.uk/forums/inde...owtopic=170486), I know his ambient temperature was a lot higher but it can't have made over 200FPS difference could it?

 

To be honest I'm not too fussed, I wanted it to shoot at 330-350 so this is a pretty good score for me right now , just need to disassemble and sort out the hop as its on permanent on at the moment.

 

So, if anyone else with one of these could share the results they got that would be appreciated.

 

Sorry for the long post

 

EDIT: I noticed a weaker recoil as well compared to when it was shooting at it's original power (430FPS), would it be feasible to cut down the buffer spring (part 92) to increase recoil?

 

Thanks in advance

Edited July 17, 2009 by tangman

[renegadecow]

EDIT: I noticed a weaker recoil as well compared to when it was shooting at it's original power (430FPS), would it be feasible to cut down the buffer spring (part 92) to increase recoil?

I was wary of this when the first pics of the TSC nozzle came out. Out of experience in trying to make my own restricted nozzle by placing spacers behind part #42, I found that its (the spacer) shape greatly affected the force of recoil as gas has to pass behind #42 to get into the piston. This is precisely why the restriction via a longer operating rod part #39 doesn't seem to affect recoil at all since the profile is so slim it hardly affects gas flow. A weaker recoil spring might work as I would advise against modifying the shape of the locking mechanism of the TSC part, but try to get hold of an RA-Tech "winter" spring because once you've cut your original spring, there's really no going back.

[rvp69]

hey tangman, i wud like to point out that i was using co2 with .28 bb's ...i have tried on propane and the results where pretty much the same,but at 25 degrees celcius. if you take the locking nut part down as much as you can( you wudnt be able to lock it as it goes below where you could fit a allen key in) you will get high fps. I do not use the stabiliser at all on the rod,i have had no problems with it ,so far..

[Eliminator]

I just received my TSC piston and installed it in my M4, after having modified it a bit. Since I use the part 42 to stay @ 350fps, I removed the adjusting power device and sanded down the threaded part. At this time, I don't know the actual fps, but it seems to be quite similar to my standard configuration. I test fired it with my 0.27g Bioval BBs, and it fired 3 full mags and 23BBs, with is pretty good, if you take in consideration that I'm using a brand new Upper set(witch also need to work itself a bit).

[somegirls]

Just a headsup. Don't buy at IPSCGM.COM.

 

I bought a barrel and a barrelnuttool with a total of $38. I paid on June 29th.

Shipping via EMS was $31 which already was more than express shipping at redwolf.

A few days ago they told me EMS wouldn't be shipping to germany what is just a plain lie, so that "had" to use standard airmail. FOR $31!!!

So finally I recieved my goods today and of course they sent me the black barrel.

I'm so frickin pi$$ by now you can't imagine.

[Eliminator]

small update about the TSC piston testing: I have an amazing result of 6 mags and 10 shots, with only 1 filling! But I had to wait betwin Mag 3 and 4, then 4 and 5, then 5 and 6+10shots, because of the cooldown of the steel nozzle. But 6 mags and 10 shots on the 7th!!!And there's still gas inside!

[tangman]

rvp, thanks, reassuring to hear

 

Thanks for the input as well Renegadecow, I have an extra Buffer Tube spring that I bought to see if cutting the spring down could increase recoil

 

-

 

My M4 has now developed a problem, everytime I pull the charging handle back, the bolt gets stuck....

 

Here's the back story.

 

At some point yesterday during the chronoing with the TSC Uni Rod, the BCG got stuck in the rear position, it would not return to the forward position.

 

So I removed the buffer tube to see if I could resolve it and managed to in the end. Everything was reinstalled back to normal and it performed like it did before, I shot about 3 more full mags (where I got the chrono results from the previous page) with no problems.

 

Later on, I noticed that the Buffer Tube wasnt on straight when I reinstalled it so I decided to straighten it.

 

I used the ACM Stock tube wrench to undo the nut and whilst doing so I slipped a few times which lead to me denting the receiver thread on the buffer tube.

 

After I got the buffer tube straightened I tried to rack the charging handle to make sure everything was fine, immedietely I noticed that I couldnt rack it all the way, there was definitely something stopping the buffer from going all the way back.

 

On closer inspection I found that the dents on the buffer tube's receiver thread came through on the INSIDE of the Buffer Tube as well. Because of these dents, the buffer couldnt slide all the way into the buffer tube anymore. I tried filing the dents down but found that completely useless so I decided to hammer the dents back out.

 

After doing that as best as I could I tested the buffer to see if it would fit. It fit, but was tight, so I installed and removed the buffer several times till it "pushed" the dents back out and so that I could get a smooth operation.

 

At the moment it seems to be as smooth as it'll get. With the buffer spring installed the buffer returns to the front position everytime. If you remove the spring and then install the buffer, then the buffer doesnt come out of the buffer tube on its own weight, you have to shake it quite hard for the buffer to come out.

 

After doing all this, I reinstalled the buffer, buffer spring, buffer tube back onto the lower receiver. I didnt bother realigning the stock tube as I just wanted to get it on quickly and test it to make sure it worked. It worked with no problems. I racked the charging handle (no mag in the M4) a good 15-20 times and each time the bolt returned to the front position with no problems.

 

I then went to realign the buffer tube and thats where the problem began.

 

-

 

Everytime you rack the charging handle, the bolt carrier gets stuck, I've tried everything I can think of but I can't find the problem.

 

The bolt moves backwards as normal but is getting caught on something when it goes to return, but I can't see or think of what it could be for the life of me.

 

If you partially rack it or rack it about 95% of the way back, it returns back as normal, but once you've racked it all the way back it gets stuck. I managed to rack it back all the way and have it return like normal just twice

 

To fix it, you have to remove the entire buffer tube assembly and then remove the rear receiver pin. Once the rear receiver pin is removed you have to pivot the upper receiver upwards so that the bolt can clear whatever its getting caught on.

 

Here are some pics of the upper and lower receivers with everything installed, am I missing anything? I can't see what it could be getting caught on at all...

 

 

 

Here are some video's which will hopefully help explain it a bit a better.

 

1. http://smg.photobucket.com/albums/v458/tan...nt=MOV00456.flv

 

Here is me racking the bolt in just the upper receiver, no problems, feels very smooth, doesnt seem to get caught on anything whilst I'm racking it.

 

2. http://smg.photobucket.com/albums/v458/tan...nt=MOV00457.flv

 

I am testing the buffer is working smoothly, again no real problem here, a bit stiff on the third time I pushed it down but that was it.

 

3. http://smg.photobucket.com/albums/v458/tan...nt=MOV00459.flv

 

Racking the charging handle, the first and second time are partial racks, third is 95% of the way back and the fourth surprisingly is all the way back. Fifth time and it gets stuck.

 

4. http://smg.photobucket.com/albums/v458/tan...nt=MOV00460.flv

 

Removing the Stock tube, here you can see the bolt stuck and caught on something.

 

5. http://smg.photobucket.com/albums/v458/tan...nt=MOV00462.flv

 

Removing the rear receiver pin and pivoting the upper receiver and then putting the Bolt Carrier back into position.

 

6. http://smg.photobucket.com/albums/v458/tan...nt=MOV00463.flv

 

A close up of the Bolt Carrier, everything looks intact to me....

 

Sorry for the essay like post and thanks for any help in advance!

Edited July 18, 2009 by tangman

[TDS]

On my rifle on the way forward it also "catches" mysteriously on something, but its not enough to stop the bolt.

 

I'm thinking that the extra rubbing plus this mystery catch is enough to stop your bolt completely.

 

I'm wondering if its getting stuck on the secondary sear? (the one behind the hammer?)

Edited July 18, 2009 by TDS

[somegirls]

Where? Somewhere like half way?

 

I think that's where the Bolt completely pushes down the hammer.

So it's either the stabilizer itself or where the bolt "continues" after the stabilizer.

[TDS]

Where? Somewhere like half way?

 

I think that's where the Bolt completely pushes down the hammer.

So it's either the stabilizer itself or where the bolt "continues" after the stabilizer.

 

Right

One way to see would be to mark the bolt and hold it right where its getting stuck on the trigger unit with the upper rec. off

 

In messing around with my rifle I had a similiar "stuck" state but that was when the trigger was "fired" and the bolt was back at the same time because I had the buffer tube off.

Edited July 18, 2009 by TDS

[somegirls]

Putting a fair amount of silicon grease on the lower/under portion of the bolt will help.

[tangman]

Cheers guys, will give all your suggestions a try

[Eliminator]

There is the solution of your problem: take a flat screw driver and simply srcew on the Buffer Retainer, it's too high.

 

Edit: Lol I didn't see your videos and saw your problem instantly...It occured on my gun too! Simply screw the Buller Retainer back in its hole and the problem will disappear!

Edited July 18, 2009 by Eliminator

[4boost]

Just got the TSC CNC hammer and sear. I used to have the problem where the valve knocker would not reset when charging the rifle. The new hammer seems to have fixed the problem as I think the little nub on the old hammer that lifts part #66 to reset the pin was worn.

[Eliminator]

4boost, you have a PM

[alston251]

hey tangman, i wud like to point out that i was using co2 with .28 bb's ...i have tried on propane and the results where pretty much the same,but at 25 degrees celcius. if you take the locking nut part down as much as you can( you wudnt be able to lock it as it goes below where you could fit a allen key in) you will get high fps. I do not use the stabiliser at all on the rod,i have had no problems with it ,so far..

 

Does that mean there isn't really much point of getting the adjustable rod if you are using green gas mags?

[1st Commando]

for those whose bolt is getting stuck during cycling , make sure the buffer tube is screwed into the receiver far enough as I have seen this problem before when the buffer tube was about 2mm too far out .

This allowed the bolt carrier to travel too far back and damage the semi cutoff lever in the process

[cocofr69]

There is the solution of your problem: take a flat screw driver and simply srcew on the Buffer Retainer, it's too high.

 

Right, Tangman just do this:

 

 

and use some thread lock ( @Eliminator vi, j'ai compris où on met le frein filet )

[somegirls]

for those whose bolt is getting stuck during cycling , make sure the buffer tube is screwed into the receiver far enough as I have seen this problem before when the buffer tube was about 2mm too far out .

This allowed the bolt carrier to travel too far back and damage the semi cutoff lever in the process

 

This might be one reason. I installed the Magpul ASAP endplate and because of its shape it misses one turn of the buffer tube.

Would something like a 2mm shim do the job?

Putting it at the end of the buffertube before the rear plastic buffer?

 

But I think I figured out the main reason:

For those who're struggling with that problem please Push the bolt stop lever OUT! What I mean by this is pushing the paddle down all the way like you'd be releasing the bolt forward.

So push it and cycle the bolt.

If it makes the problem dissappear let me know! (So we can find a solution)

[tangman]

There is the solution of your problem: take a flat screw driver and simply srcew on the Buffer Retainer, it's too high.

 

Edit: Lol I didn't see your videos and saw your problem instantly...It occured on my gun too! Simply screw the Buller Retainer back in its hole and the problem will disappear!

 

Right, Tangman just do this:

 

http://www.imagefreehost.com/files/1907200...1169093353.jpeg

 

and use some thread lock ( @Eliminator vi, j'ai compris où on met le frein filet )

 

Thanks guys, unfortunately it's not the buffer retainer, I have screwed it as far down as possible and it's still happening

 

for those whose bolt is getting stuck during cycling , make sure the buffer tube is screwed into the receiver far enough as I have seen this problem before when the buffer tube was about 2mm too far out .

This allowed the bolt carrier to travel too far back and damage the semi cutoff lever in the process

 

AND WE HAVE A WINNER!

 

x 100000000

 

Thanks to everyone who helped, hope this helps someone else in the future!

[TrooperX]

Used my M16 at a skirmish for the first time today. Only had .25g bb's - they flew about 20m straight and then just went vertical - this was with the hop wound right off! Same for mates CQBR. So it was pretty unusable like that and I will be trying heavier bb's next time.

 

I have a problem with 2 out of my 5 mags where the plastic bb follower gets stuck about the 3rd of the way down in the channel. I took one apart and the plastic follower moves in the channel ok without the spring but fitting the spring and its get stuck on the way down. Need to have a closer look at this but I'm wondering if I need to dremel out some of the channel to allow the follower to move easier. BTW - refitting the spring is a *badgeress*!!!

 

None of my mags lock back on empty - it looks like the little nubs that activate the bolt catch don't protrude enough. I've ordered a replacement one from airsoft123 and if that sorts it I'll buy some more.

[TDS]

Hopup is crazy until you put a few thousand rounds through yours, until then just use the heaviest bb's you can get ahold of

 

Haven't had the channel issue, the stock maglocks wear very quickly

[Nazio]

For now i have lost semi auto at all. Constant burts of two shots. Mag is falling during shooting. Dunno if this has anything common with #83 or #75 or something else. Fps is back in full strengh, so i have to buy UDGR from Airsoft123. Wondering if previous chronograph wasn't broken or something.

Edited July 19, 2009 by Nazio