Tippmann M4 not firing

[MisterG]

So hose arrived early this morning.  Hooked it all up, gun does not fire.  The tank has about 1400 psi, which I assumed would be enough.

I can pressure the hose, cock the gun and put when I pull the trigger the mechanical parts move, but doesn't sound like the gun is getting any pressure to fire a BB. 

I can't hear any obvious leaks.

I have a ninja hose, as it was recommended on the forum.

Any ideas?

Cheers

G

 

[L3wisD]

Hmmm.. could be the valve isn't getting the air.

Can you split the recievers open and upload some photos of inside the upper. The charging handle, valve area.

And pop your trigger assembly out and a photo of that too.

Also, a photo of the recoil bolt in the buffer.

If the recoil weight is protruding into the lower reciever too much the gun won't cycle.

 

[MisterG]

This is a video of how it looks now.  I'll take the photos in a bit.  I went back to the Diving shop and filled the cylinder in case there wasn't enough pressure, other cylinder was ready, needed an new O ring.

The mechanical bits seem to work, i.e. and can cock and fire it, as per the video.

View attachment 34997

 

[MisterG]

These are the pics I took.

Cheers

G

View attachment 34998

View attachment 34999

View attachment 35000

View attachment 35001

View attachment 35002

I think there is a small airleak between the connector in the grip and the top of the main air line as I can hear air escaping if I blow into it and cover the end of the air line in the receiver.  But it still blows enough air that I should at least see a BB come out when firing.  I'm assuming I blow less than 800 psi?

 

[gasman]

I can see that the plastic part that pushes the bb into the barrel is engaged. It should return after each shot the u shaped wire rod should engage in a slot on top of the plastic part, who assembled it?

looks like the gun snuff was selling

can you see it move when you fire it

 

[MisterG]

Not sure, perhaps the previous owner.  I just bought this used, only got a chance to test fire today, as had to wait for an HPA hose. 

I just had the barrel off and there were about 6 BBs jammed together in the bucking/end of the barrel with the bucking.

How do I unjam that?

Cheers

G

 

[gasman]

normal plastic rod will push out the bbs. Sounds like the hop adjustment is way to tight, has it got the tdc upgraded hop adjuster or standard. the gun should fire with pressure as low as 800 psi.

when you turn the air on the bottle screw gently all the way then back 2 turns. Sometimes if screwed all the way it restricts air.

there are adjustments on the trigger assembly that can be made if in doubt return them to stock settings. the only other thing to do is strip the gun and check part 14 which is the valve assembly in the upper make sure that someone has not fitted the air saver part which if to thick stops it from firing. the fps adjustment screw if set wrong can cause non firing start with it all in

 

[MisterG]

I took out the BBS, completely removed the Hop up screw, looks like it was too tight, bucking is slightly deformed.

Gun is stock, no mods.

tried your tip re the bottle, and scared myself sh|tl3ss when it started firing.  Only dry fired it, but not used to that level of noise and blow back.  Didn't have the supressor on and the inner barrel vibrated a lot.

I'm not sure if there is an issue with the hose, the bottles or I am not using them right.  I can't depressurise one of them, and the other has no O ring at the top.

 

[gasman]

I found that the pressure release on the hose where it connects to gun can be very tight when new due to no lubrication if you are struggling to pull the black ring back a couple of drops or silicon lubricant on exterior will help it slide. To connect bottle to ninja line screw bottle into ninja line until seated a little molycote 33 smear on the oring does help screw top in till seated then backoff 1.5 to 2 turns. Push connector onto gun connector in doing so slide release ring forward done. to remove slide ring rear ward to release air and remove. the vibration is not the inner barrel but the return spring in the stock tube they are renowned for this.

The bucking needs to be  a tipmann original or G&G green. They perform well when flat hopped with the TDC mod but mod works well with green bucking.

safety note never use normal oil on HPA it has the potential to explode

Do not fit a heavy bolt they are crap and break the gun. A madbull 6.03 works great in tipmanns. heavy silicon grease on spring in stock tube will quieten slightly. Ptfe is not required on upper threads.

Play with all the adjustments  guided by the better youtube techs some of them are crap. fit the TDC mod that fits straight in using the normal hop screw not the type you drill or the longer 3D printed one.

After all that and a week playing with adjustments and you have a super performing gun. Fps from 0 to 550 FPS

note I have modded the trigger assembly so it only fires semi as DMR using 3.0 BBs

 

[MisterG]

Big thanks to @L3wisD and @gasman and the chap at the Dive Shop.

After a bit of maintainance and a couple O rings on the HPA cylinders and resolving an operator error (I did RTFM, but the hose didn't come with one ?) I am now shooting BBs \o/.

My test range is only 5m but seems fine.  Will try out on Sunday outdoors, before I start modding anything.

But have already taken a lot of it apart.

Recoil and sound brings a whole new element to the experience.

Cheers

G

 

[L3wisD]

The noise and the recoil on the Tippmann is so fun. Loved mine

Also, I'll echo the advice about greasing the buffer tube spring.

Greased mine with Abbey LT2 Grease and the horrible "PHHWOOOAANNG" noise disappeared almost entirely. Much better.

Americans and that will tell you that real ARs are supposed to have the twanging sound though. ?

 

[MisterG]

I probably need to get some more grease, I bought the Basic Parts kit, it did come with some grease, about 3mm thick and the size of a thumbnail.

I've also got PFTE grease and Silicon Grease.

Cheers

G

 

[snuff]

Yes it was the one I sold..I know it's history but I am clueless with HPA,luckily there is a helpful knowledge base on here,thanks for helping him out everyone.................................glad it's sorted G have fun..

 

[MisterG]

The noise and the recoil on the Tippmann is so fun. Loved mine

Also, I'll echo the advice about greasing the buffer tube spring.

Greased mine with Abbey LT2 Grease and the horrible "PHHWOOOAANNG" noise disappeared almost entirely. Much better.

Americans and that will tell you that real ARs are supposed to have the twanging sound though. ?

Got the grease, lubed up the spring and the twang is gone. 

Did a service while I was at it, took apart the trigger put silicone grease on some O-rings, fixed my hose which starting leaking last week (dodgy O-ring- I don't seem to have much luck with O-rings ?)

All firing good again.  Flat hopped as well. Now if fixing my G36C was as easy....

Cheers

G

 

[michael1983]

These are the pics I took.

Cheers

G

View attachment 34998

View attachment 34999

View attachment 35000

View attachment 35001

View attachment 35002

I think there is a small airleak between the connector in the grip and the top of the main air line as I can hear air escaping if I blow into it and cover the end of the air line in the receiver.  But it still blows enough air that I should at least see a BB come out when firing.  I'm assuming I blow less than 800 psi?

how much for your trigger unit cheers

 

[MisterG]

Hi

As I managed to solve the problems, I have a fully working gun so I won't be selling the trigger separately.

Cheers

G

 

[lol]

Did u see if the gun was cocked...has to be for it to fire