More accessories added
Metal barrel as well
@bme Would the metal barrel help increase the fps?
Hmmmā¦
I think the 14.3 cm metal barrel, is simply a replacement for the original plastic barrel.
As such, it would not really make any difference.
Lengthening the barrel further beyond that, may improve fpsā¦butā¦ the volume of the cylinder just isnāt that large.
The only way to find out is to tryā¦get a longer barrel and install it. Youād then have a tip protruding. The new outer barrel would cover thatā¦but they donāt sell them seperately.
I have a barrel extender from the mp5-k.
Iāll see if that fits tightly onto the tec-9, and if it makes any differenceā¦
EDIT: i just re-read my previous posts from aboveā¦
i tried a metal barrel, about 3cm longer which i was able to get a pretty good air seal on.
It made no differenceā¦
Tiny cylinder, i reckonā¦160 fps it isā¦
I might have to get another b709a and get the black tactical tec-9 and see about a longer barrel, but that still leaves the cylinder to upgrade, which if memory serves correct you said it was a proprietary cylinder didnāt you?
Do you think there would be a work around to beef up the cylinder somehow?
Get another cylinder and and customise it somehow to fit but still improve performance?
BMEās pics
Would there even be something suitable to replace the guts of the cylinder?
When your talking increasing performance, a key core concept ( for AEG) is matching the cylinder size to the barrel length.
i.e. take a āstandardā V2 gearbox.
It has a full size cylinder, of a certain swept volume.
It is also of a certain physical sizeā¦ it will physically fit into full size rifles, and can just fit into smaller SMGās ( ie mp5-k).
Now, for that V2 cylinder, there is an optimal barrel length.
Too short, the gel does not get to spend enough time being accelerated in the barrelā¦lower fps results.
Too longā¦( think really , really long)ā¦ it accelerates to its max fpsā¦but then the walls of the barrel actually start to slow it downā¦it gets subject to drag from the walls, having reached its maximum velocity.
Other gains can be had by āimproving the systemāā¦ ie stronger spring, sealing air leaks etcā¦ but the core components are volume of cylinder, and barrel length.
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So, with the tec-9ā¦ its got its own , custom made to fit in the shell gearboxā¦with a small cylinder.
Small shell body = small cylinder.
It will be nearly impossible to shoehorn any other gearbox in, so were stuck with it.
Also, the blaster is very cheaply made , $10 US, so it has a weak plastic gearbox, plastic gears etc.
This means trying to upgrade the spring for higher performance would probably blow everything up, in a short period of time.
I did put on the barrel extender last night (pics up later).
That extended the plastic barrel by 3-4 cm, with a tight airseal.
Results variedā¦ i did see some 180 and 190 fpsā¦but also 130 and 140.
It was all over the place.
Barrel back to normalā¦back to consistent 155 fpsā¦
You can upgrade the spring, that would give you higher fpsā¦but would also break something fairly quickly, i imagine.
If we got em for $10ā¦sure do it for shits and giggles, till it breaksā¦but iām sure you dont wanna wreck yours.
Soā¦it pretty much looks like āit is what it isāā¦ apart from trying to improve airseals, you cant really do a lotā¦
Limited by its small, custom fitting gearboxā¦
And, a shorter barrel, which terminates inside the shellā¦
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Might be worth looking at the piston seal in that gearbox. My guess is itās a cup seal.
Just like o rings, if the sealās held in a compressed state for a while it will take on a memory and have a less than great seal against the cylinder wall.
If it is a cup seal you could try dunking it in boiling water for a few seconds and teasing it out, might expand slightly and give you a better airsealā¦ who knows? 
Just be careful pulling that box apartā¦ ones like that are full of small springloaded plastic bits that go boing-ting when the shell halves are split. 
Thats why people got excited about the v2.5 gearboxā¦its a larger gearbox, with a larger swept volume.
The v2 is a āstandard boxā, and has been around for awhile.
It goes into many different blastersā¦but its the same engine, providing the same performance levelā¦nothing really new, performance wise for some timeā¦
The V2.5, as found on the E&C DMRās are a larger gearbox.
More swept volume, more air being pushed per cycle, allowing matching to longer barrels, for more range and performance.
@Friendly_Fire and i saw one at vipertac ( when it was still open).
I fired it indoors, inside their large warehouseā¦it was travelling and hitting the upper corner of the roofā¦ around 40+m awayā¦and fairly accurate.!
Good bit of kitā¦but lends itself to larger rifles, due to the larger size of the cylinder, and longer barrel requiredā¦
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Worth noting too that a full size cylinder with all the airseal upgrades in an MP5K only showed 220FPS on the chrono, a gain of about 20FPS.
Itās all in the barrel length. An extension to that barrel showed 280+ on the clock, so proved that the upgrades were working. But take off the inner barrel extension and 220 again.
Which means even if you could fit a larger setup into that Tec-9, youād see no appreciable gains.
Itās just one of those āenjoy it for the form factorā blastersā¦ canāt really be upgraded, much like the Le Hui MP9s, but looks cool nonetheless.
An all metal, gas blow back version would be a different storyā¦
They have em in airsoftā¦who knowsā¦
If these sell out well, they might consider a GBB import one day.
If not, these are better than nothingā¦!!
Iām very, very interested to see what sort of difference the upgrade spring does, to the P320 pistolā¦
It should be here soonā¦
Thatās a little disappointing
I suppose itās just a case of it is what it is then I guess.
I know I would be keen the have one in full metal GBB form
Hopefully one day 
Apparently mp9 gearbox can be shoehorned into the TEC-9, apparently
Would that be this one?
Does appear to be appropriately sized, and reasonably priced
Thatā¦sounds like a self imposed challengeā¦!!
Goā¦!!
Donāt trust Aiā¦
Donāt trust Gbuā¦!!
Double bungerā¦!!
yeah not too hard to do, theres videos of it on bilibili: example
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Page wonāt load for me
works fine for me, weird.
Cool.!
Wasnāt sure it that gearbox would fitā¦but it does.
I wonder how much he had to modify the shellā¦obviously chinese audio.
Anyway, its do-ableā¦ and MP-9 gearbox would be one step up from the supplied one.
MP-9 does 190-200 fps right out of the box , so thats the figures were looking for.
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