CA B&T Metal Body Air Seal Issue.

DarkAngel · January 26th, 2010, 01:49

Alright, this issue has been plaguing me since I went FMU with my TM MP5.

I scored one of the Last CA B&T Metal bodies made by Classic Army designed Specifically as an FMU Kit for TM Guns.

The new CA Hop up's for MP5 no longer uses the Lever style system in traditional TM MP5 Hop up Units. It uses a slider similar to the TM AK hop ups.

While the TM Hopup is screwed into the plastic TM Bodies using two screws, while the CA New Type MP5 Hop up is a Metal Slider stype hop up. It is not screwed into the body at all. In fact there is nothing holding the hop up inside the body other than the gearbox pressed up against it.

The box has been tested and has a very good compression rate, Ive ruled out the Gearbox itself. However, There appears to be an airseal leak between the gearbox and the Hop up Chamber due to the movement (approx 1/2 a cm movement) I had attempted to wrap the hop up unit (the tube section just after the clip) with teflon tape, so that when the two halves of the MP5 body clamp firmly onto the hop up unit. I also applied a thin layer around the hop up hole to attempt to reduce the airloss. While this solved the issue temporarily, my victory was short lived. I began to lose airseal again and after layering a little more teflon tape, it began to affect the feeding of the gun as the gap between the gearbox and the hop up unit was great enough that it now double feeds.

Conclusion, Stuffing the gap between the box isnt working. I need to find a new solution to mount the hop up chamber better, with no proper method of mounting, im at a loss. Anyone got any solutions the can suggest?

cerealmaniac · January 26th, 2010, 02:20

just wonder if you have the metal front end too. mine has tabs that secures the barrel + hop up.

Skladfin · January 26th, 2010, 02:29

Is the hop up unit not FAR BACK enough? or is it not forward enough? or is it just simply moving back and forth randomly?

DarkAngel · January 26th, 2010, 11:26

Yes, I am Using the CA Cocking Tube + Assmby. Which Tabs are you referring to?

its got about 1/2 a cm play between the body and the gearbox. But the IB and Hop needs to be pressed backwards against the gearbox.

Amos · January 26th, 2010, 11:42

Have you tried adding a spring or something around the outer barrel to force the hopup unit back against the mechbox?

What rubber are you using?

Skladfin · January 26th, 2010, 11:49

-slide in O-rings onto the IB just in front of the hop up unit to have it sit back more. And if it moves too far back, shim the gearbox with tape or something of the similar.

or

-Modify the tappet plate like so:
http://www.airsoftcanada.com/showthread.php?t=92666

or

-Get a longer air nozzle that is long enough to reach but not enough to cause misfeeds.

DarkAngel · January 26th, 2010, 12:10

Im already shimming it with teflon tape. Its a method I do not personally approve of using and rather was a quick fix to get it up and running for 3-4 games. Last thing i want is to shim it more.

The way the hop up sits in the CA Body, Orings, Washers etc would not work.

Which brand nozzel had the Oring on the outside of the nozzel again for better hop up airseal?

Im using Guarder Clears, On TM Stock Inner. The gun "should" be shooting just under 350 based on the internals I put in. If it does, ill be putting in a TK twist, if its higher, ill put in a prom .03

coach · January 26th, 2010, 12:30

I have a similar issue with mine. I'm using a stock TM box with all Modify internals so the box is sound as well.

I'll have to open it up and try to be creative.

Amos · January 26th, 2010, 14:09

Have you checked your nozzle against a CA nozzle?

Crunchmeister · January 26th, 2010, 14:38

I think Amos might have a point. I think the CA nozzle might be just a hair longer than the standard TM.

I had this same issue with my JG when I upgraded to the CA body. Originally, I had the stock JG hopup unit (you CAN fit a TM lever hopup unit in there) with the CA body because the body I bought didn't come with a hopup. When I finally got the CA metal hopup, I dropped from 330 fps down to 210 fps... Tried everything. No change.

What I did was looked through my box of 'mystery parts' and found a nozzle that was slightly longer (estimate about 1mm) than the standard JG MP5 nozzle. Installed that just to try. Now the gun is firing a consistent 340-350 fps and it's a nail driver.

Good luck

coach · January 26th, 2010, 14:59

Good point on the CA nozzle fellas! Will have to look into that or just dig through the box of bits and find one slightly longer.

Crunchmeister · January 26th, 2010, 15:03

I wish I knew what kind of nozzle I had. I just placed them side by side, and the mystery one was a touch longer. But I'm sure if you could find the proper CA nozzle, the problem would be fixed.

DarkAngel · January 26th, 2010, 17:02

Ill give that a shot

DarkAngel · January 29th, 2010, 16:12

Fixed, Im a retard. Milehigh Pm'ed me about this.

When i received the receiver, I left a piece out due to not knowing where it was supposed to go. (The kit doesnt come with instructions of any kind). So I left it in the box and completely forgot about it. After installing the piece (A Sleeve for the hop up unit that screws into the body) and removing ALL of the teflon tape, the gun doesnt seem to have any sealant issues (Though I have yet to chrony i for airseal confirmation).

SHÖCK · January 29th, 2010, 21:06

Good to hear that it works. So your body is the old type that doesn't have a sliding ejection port?

I'd love a CA body with the ejection port working with the cocking lever even with the hop-up as TM style on the outside of the cocking tube.

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January 26th, 2010, 01:49	#1
DarkAngel * Age Verifier status suspended * Trader rating Join Date: Jun 2006 Location: Scarborough	CA B&T Metal Body Air Seal Issue. Alright, this issue has been plaguing me since I went FMU with my TM MP5. I scored one of the Last CA B&T Metal bodies made by Classic Army designed Specifically as an FMU Kit for TM Guns. The new CA Hop up's for MP5 no longer uses the Lever style system in traditional TM MP5 Hop up Units. It uses a slider similar to the TM AK hop ups. While the TM Hopup is screwed into the plastic TM Bodies using two screws, while the CA New Type MP5 Hop up is a Metal Slider stype hop up. It is not screwed into the body at all. In fact there is nothing holding the hop up inside the body other than the gearbox pressed up against it. The box has been tested and has a very good compression rate, Ive ruled out the Gearbox itself. However, There appears to be an airseal leak between the gearbox and the Hop up Chamber due to the movement (approx 1/2 a cm movement) I had attempted to wrap the hop up unit (the tube section just after the clip) with teflon tape, so that when the two halves of the MP5 body clamp firmly onto the hop up unit. I also applied a thin layer around the hop up hole to attempt to reduce the airloss. While this solved the issue temporarily, my victory was short lived. I began to lose airseal again and after layering a little more teflon tape, it began to affect the feeding of the gun as the gap between the gearbox and the hop up unit was great enough that it now double feeds. Conclusion, Stuffing the gap between the box isnt working. I need to find a new solution to mount the hop up chamber better, with no proper method of mounting, im at a loss. Anyone got any solutions the can suggest? __________________ Certified Sniper Clinic Instructor and Counter Sniper Sentinel Arms Customs - Specializing In Unique, One of a kind guns

January 26th, 2010, 02:20	#2
cerealmaniac Trader rating Join Date: Jun 2008 Location: Alberta	just wonder if you have the metal front end too. mine has tabs that secures the barrel + hop up. __________________ 飛虎隊 NEED ANY OLD/USED AK/MP5 PARTS!PM ME! Sales Thread Click Me AEG sales thread Last edited by cerealmaniac; January 26th, 2010 at 02:43..

January 26th, 2010, 11:26	#4
DarkAngel * Age Verifier status suspended * Trader rating Join Date: Jun 2006 Location: Scarborough	Yes, I am Using the CA Cocking Tube + Assmby. Which Tabs are you referring to? its got about 1/2 a cm play between the body and the gearbox. But the IB and Hop needs to be pressed backwards against the gearbox. __________________ Certified Sniper Clinic Instructor and Counter Sniper Sentinel Arms Customs - Specializing In Unique, One of a kind guns

January 26th, 2010, 02:29	#3
Skladfin Trader rating Join Date: Dec 2006 Location: Glace Bay, Nova Scotia	Is the hop up unit not FAR BACK enough? or is it not forward enough? or is it just simply moving back and forth randomly?

January 26th, 2010, 11:42	#5
Amos Trader rating Join Date: Aug 2006 Location: Tokushima, Japan	Have you tried adding a spring or something around the outer barrel to force the hopup unit back against the mechbox? What rubber are you using? __________________ Custom Builds: FA3674U Krinkov G3SD6

January 26th, 2010, 11:49	#6
Skladfin Trader rating Join Date: Dec 2006 Location: Glace Bay, Nova Scotia	-slide in O-rings onto the IB just in front of the hop up unit to have it sit back more. And if it moves too far back, shim the gearbox with tape or something of the similar. or -Modify the tappet plate like so: http://www.airsoftcanada.com/showthread.php?t=92666 or -Get a longer air nozzle that is long enough to reach but not enough to cause misfeeds.

January 26th, 2010, 12:10	#7
DarkAngel * Age Verifier status suspended * Trader rating Join Date: Jun 2006 Location: Scarborough	Im already shimming it with teflon tape. Its a method I do not personally approve of using and rather was a quick fix to get it up and running for 3-4 games. Last thing i want is to shim it more. The way the hop up sits in the CA Body, Orings, Washers etc would not work. Which brand nozzel had the Oring on the outside of the nozzel again for better hop up airseal? Im using Guarder Clears, On TM Stock Inner. The gun "should" be shooting just under 350 based on the internals I put in. If it does, ill be putting in a TK twist, if its higher, ill put in a prom .03 __________________ Certified Sniper Clinic Instructor and Counter Sniper Sentinel Arms Customs - Specializing In Unique, One of a kind guns Last edited by DarkAngel; January 26th, 2010 at 12:50..

January 26th, 2010, 12:30	#8
coach aka coachster Trader rating Join Date: Mar 2008 Location: T dot	I have a similar issue with mine. I'm using a stock TM box with all Modify internals so the box is sound as well. I'll have to open it up and try to be creative.

January 26th, 2010, 14:09	#9
Amos Trader rating Join Date: Aug 2006 Location: Tokushima, Japan	Have you checked your nozzle against a CA nozzle? __________________ Custom Builds: FA3674U Krinkov G3SD6

January 26th, 2010, 14:38	#10
Crunchmeister Trader rating Join Date: Nov 2007 Location: In your bedroom going though your underwear drawer	I think Amos might have a point. I think the CA nozzle might be just a hair longer than the standard TM. I had this same issue with my JG when I upgraded to the CA body. Originally, I had the stock JG hopup unit (you CAN fit a TM lever hopup unit in there) with the CA body because the body I bought didn't come with a hopup. When I finally got the CA metal hopup, I dropped from 330 fps down to 210 fps... Tried everything. No change. What I did was looked through my box of 'mystery parts' and found a nozzle that was slightly longer (estimate about 1mm) than the standard JG MP5 nozzle. Installed that just to try. Now the gun is firing a consistent 340-350 fps and it's a nail driver. Good luck __________________

January 26th, 2010, 14:59	#11
coach aka coachster Trader rating Join Date: Mar 2008 Location: T dot	Good point on the CA nozzle fellas! Will have to look into that or just dig through the box of bits and find one slightly longer.

January 26th, 2010, 15:03	#12
Crunchmeister Trader rating Join Date: Nov 2007 Location: In your bedroom going though your underwear drawer	I wish I knew what kind of nozzle I had. I just placed them side by side, and the mystery one was a touch longer. But I'm sure if you could find the proper CA nozzle, the problem would be fixed. __________________

January 26th, 2010, 17:02	#13
DarkAngel * Age Verifier status suspended * Trader rating Join Date: Jun 2006 Location: Scarborough	Ill give that a shot __________________ Certified Sniper Clinic Instructor and Counter Sniper Sentinel Arms Customs - Specializing In Unique, One of a kind guns

January 29th, 2010, 16:12	#14
DarkAngel * Age Verifier status suspended * Trader rating Join Date: Jun 2006 Location: Scarborough	Fixed, Im a retard. Milehigh Pm'ed me about this. When i received the receiver, I left a piece out due to not knowing where it was supposed to go. (The kit doesnt come with instructions of any kind). So I left it in the box and completely forgot about it. After installing the piece (A Sleeve for the hop up unit that screws into the body) and removing ALL of the teflon tape, the gun doesnt seem to have any sealant issues (Though I have yet to chrony i for airseal confirmation). __________________ Certified Sniper Clinic Instructor and Counter Sniper Sentinel Arms Customs - Specializing In Unique, One of a kind guns

January 29th, 2010, 21:06	#15
SHÖCK aka SNK or Shaniqua Trader rating Join Date: May 2008 Location: Calgary, AB	Good to hear that it works. So your body is the old type that doesn't have a sliding ejection port? I'd love a CA body with the ejection port working with the cocking lever even with the hop-up as TM style on the outside of the cocking tube. __________________ SHÖCK Last edited by SHÖCK; January 30th, 2010 at 02:03..

CA B&T Metal Body Air Seal Issue.

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