Let's Unfuck a Brand New Action Army T-11: a Build Log in Case Anyone Wants to Make a 1j Build Out of This Thing

[Skara]

Yo it's-a me, Skara!

 

Just picked up this gun as a replacement for my striker.

I like it a lot, super balanced, lightweight, bolt pull is a million light years ahead of the striker, mags are tiny and hold 50 rounds, I like the trigger design with the sear that rotates instead of being pulled down, makes for a very crisp trigger pull.

 

My plan for this gun was to replace the piston with an airbraked one (stock polymer piston is fine for 1J but I want it silent), fit a sorbo, change the hop rubber, install a TDC and give it a bit of an internal suppression using a shorter inner barrel while filling the outer with foam and/or other sound dampening materials.

 

This is where it went wrong, somehow:

 

At first, the cylinder head was an utter cunt to remove, managed to do it without ruining it too much, sorbo installed and it is a smidge quieter, the stock has been filled with foam and cotton wool in every void possible apart from the fake magazine well as I need to come up with a more clever solution for that.

 

My biggest issue is now the hop up.

The chamber itself isn't bad, it's the standard TM style chamber but there are two main differences:

- The adjustment system now has notches in which a sprung loaded ball bearing slots into, effectively locking the adjustment in the position you leave it;

- The hop arm has an integrated concave tensioner, great for R-Hop/Maple Leaf rubbers on paper.

Now, the hop is on-off for me, it either doesn't lift anything or it straight up jams.

I thought it was the hop rubber being not-so-great, so I replaced it with a trusty Maple Leaf MR-Hop...

Now one would expect to be able to lift rocks, but nope  it still does the same, nothing-nothing-nothing-jam.

 

Trying to find the cause of this issue at the moment, but if we analize what actually happens inside an airsoft springer (AEGs even, it's the same thing):

-The piston compresses the air inside the cylinder
-The air inside the cylinder escapes through the nozzle
-The nozzle is (supposedly) sealed in the hop rubber
-The air coming out of the nozzle pushes the BB under the hop rubber's contact patch, giving it backsping
-BB leaves the barrel

 

Between these steps, something goes Chernobyl levels of wrong 😕 but for the life of me I can't figure it out

 

Any input?

[Adolf Hamster]

ordinarily the issue i'd be thinking is still the hop, maybe the level of adjustment is sufficiently course that in the space of a click you're going from not enough tension to do shit to enough tension to jam? you might have a better idea by feel wether or not that's a possibility.

 

normally before reassembling any gun i tend to turn the hop off/on whilst looking down the barre just to be sure it's all moving right and the rubber is sitting nice and square.

[Shaydee]

Yeah like @Adolf Hamster I'd be checking the hop/inner barrel assembly first. Ideally out of the gun and checking there are no obstructions with the unit going from off to fully on, popping a BB in and seeing if it'll pass through without having to use a metric fuckton of force.

[Skara]

I did check the fitment when installing the rubber and it was working fine.

Being a MR-Hop it requires a smidge more pressure than a "regular" Maple Leaf as the patch design mimics the inner barrel (and actually rests on it).

 

One theory would be that the T-10/T-11 chamber really doesn't like the MR rubber - I'll try with the new 2021 silicone Decepticon I bought not long ago.

 

2nd theory: the hop arm has a too long integrated tensioner that pushes the front part of the hop rubber way too deep. It's a hinged design so naturally the muzzle end of the tensioner contacts the rubber much earlier than the rear end, this could make the rubber protrude too much, clogging the barrel. To be honest I haven't really checked the hop arm, will do tonight and if theory #1 doesn't work, I might remove a small portion of the tensioner.

 

3rd theory (unlikely): there is just not enough pressure to push the bb past the contact patch. The stock piston is REALLY light (think 20 grams or so) and the spring is quite soft too as it puts out 0.75J on average.

 

4th theory (also unlikely): there's something wrong with the stock barrel. Luckily I have a 6.03x300 AA steel barrel so I can try swapping that too.

 

I have a SCW piston on my way along with a gunsmithy TDC (the €30 set with the hop arm) so I don't really mind modifying the stock arm for science.

 

Many people suggested to buy the red AA chamber, but it's expensive as hell at €60 and seems way too complicated to properly set up.

 

And of course I'll go mad on PTFE around the rubber and check for every possible air leak to eliminate any variable.

[Skara]

Theories #1 and 2 are wrong.

The hop arm is fine, the integrated tensioner is just a hair longer than a regular omega and it applies nice, even pressure to both the MR and Decepticon rubbers.

 

Testing theory #4 right now.

 

Update:

Theory #4 didn't work.

 

Considering that the piston is super lightweight (sub 20 grams I would say) I think theory #3 could be the one.

 

Oh well, I'm gonna have to wait until the new piston arrives and test again

Tomorrow I'll go shopping for foam sheets and other materials I need for the internal suppression (cup drill bit mainly).

[Samurai]

If you are shooting heavy balls, you'll need the softest rubber you can find and if you can put something soft between the bucking and the hop arm, that helps too.

1J gun would need 50 hardness bucking even with 0.2g bbs. Heavier ones would like it even softer.

[Skara]

0.3g bbs can't really be called "heavy".

Okay they may be heavy at 1J, but the striker definitely lifts them.

The Decepticon currently installed is a 60, but it's the 2021 silicone version so it's 55° really (almost as soft as the 50° in my aap).

[Skara]

Smol apdeit.

The new rubber seems to lift them 0.3s just fine.

Now though the power has dropped from 0.79/0.8J to barely 0.6J and really poor range @barely 40 metres, methinks it's because of the sorbothane pad in conjunction with the aforementioned lightweight piston + weak spring.

 

SCW piston has been posted, it says delivery within 5 days but knowing Poste Italiane it'll probably be 5 weeks.

 

Since I'm going to the hardware store I'll also pick up an extra roll of solder, later I'll try to add weight to this plastic piston and see what happens

[DerDer]

3 hours ago, Skara said:

0.3g bbs can't really be called "heavy".

Okay they may be heavy at 1J, but the striker definitely lifts them.

The Decepticon currently installed is a 60, but it's the 2021 silicone version so it's 55° really (almost as soft as the 50° in my aap).

It's debatable . Going by retailers, good percentage label anything above 0.28g as heavy. 

 

Hop up rubber degrees are another where there seems to be a bit of differing standards. One crowds 50 is equivalent to another's 55. 

Then look at the recommendations for joule output and applications, you would be fit to rip out you hair. 

 

 

[Adolf Hamster]

6 hours ago, Skara said:

Okay they may be heavy at 1J

 

*looks at bag of 0.48's*

 

*looks at 1j SVD*

 

[DerDer]

27 minutes ago, Adolf Hamster said:

 

*looks at bag of 0.48's*

 

*looks at 1j SVD*

 

This year went heavier than 0.25, the 0.28g were great performers. Promptly ordered a dozen bags. Then tried 0.30g, even better. 

Have set a limit on 0.32g, as they were even better again.  Can delude myself that I'm keeping the 0.28 for the support gun.  

[Adolf Hamster]

49 minutes ago, DerDer said:

This year went heavier than 0.25, the 0.28g were great performers. Promptly ordered a dozen bags. Then tried 0.30g, even better. 

Have set a limit on 0.32g, as they were even better again.  Can delude myself that I'm keeping the 0.28 for the support gun.  

 

it's quite the rabbit hole, especially when you've saved up a bunch of bags of .48's all year and burn them all in a day with the polarstar then realise "holy shit i've just burned 3 figures worth of ammo )

 

hence shifting to the dragonuv, doesn't feel so bad when your day's round count is only 160 shots to be splashing out on the heavies.

 

although .32 is now my default weight, if a gun can't handle .32's then i make sure it can.

[Skara]

The issue I have has nothing to do with bb weight or rubber hardness.

 

It's about the piston being too light and the system not giving enough pressure to push the bb past the hop.

 

The piston itself is 15 grams, yes, F I F T E E N fucking grams, no wonder it can't push shit

wrapped about 20 grams of solder around it and taped, now it is 35g and change, which upped the power by 0.2something J, clocks in at 0.85J now.

Can't test the hop/range as it's too dark to see anything, but hopefully the system will now have enough pressure to let me plink at the neighbor's roof.

 

I have some 0.32s, will give them a go tomorrow (also have some 0.4s but they are dark grey which makes it hard to track them)

[DerDer]

On 19/12/2020 at 15:30, Adolf Hamster said:

 

it's quite the rabbit hole, especially when you've saved up a bunch of bags of .48's all year and burn them all in a day with the polarstar then realise "holy shit i've just burned 3 figures worth of ammo )

 

hence shifting to the dragonuv, doesn't feel so bad when your day's round count is only 160 shots to be splashing out on the heavies.

 

although .32 is now my default weight, if a gun can't handle .32's then i make sure it can.

That's impressive in a way to go through that amount of ammo. Fair point as regards the .32, it's a good weight. Have about two guns set up with 0.28s. Picked up two bottles of devil blaster in 0.30g. Don't think I will bother after they are gone, getting any more . Find 0.28g decent for the wallet and 0.32g for raw performance.  

[Adolf Hamster]

Yeah it was amazing, basically easy mode for the day, but needless to say not a sustainable way to play.

[Skara]

 

 

So, all the parts arrived.

Just need to pick some 2 part epoxy to glue the TDC base

 

That piston is an absolute work of art though ❤️

[Skara]

I am honestly confused.

I thought airbrakes were meant to quieten the gun, not making it noticeably louder 😕

 

I'm starting to think I made a terrible mistake..

[Adolf Hamster]

Is it piston slap or barrel pop?

 

Even if the action is silent there can still be a lot of noise from the barrel especially on a shorter barrel.

 

Fortunately thats where airsoft suppressors do actually do a good job.

[Skara]

Clear, loud piston slap.

It seems like the airbrake doesn't do its job, probably because the cylinder head is tapered.

I'm gonna pop SCW a message and see what he/they say.

[Adolf Hamster]

23 minutes ago, Skara said:

Clear, loud piston slap.

It seems like the airbrake doesn't do its job, probably because the cylinder head is tapered.

I'm gonna pop SCW a message and see what he/they say.

 

could be, sounds like the kind of part that really should be matched to it's cylinder head.

[Skara]

 

Crap picture, but it should give you the idea.

I think that because of the tapered design the airbrake cannot physically plug the nozzle when it's supposed to, so the piston just slams with full force against the cylinder head.

 

@alxndrhll

Here it is  cylinder head, stock piston, weighted SCW from left to right.

 

sorry for the spam but it's bugging me.

[Adolf Hamster]

44 minutes ago, Skara said:

 

I think that because of the tapered design the airbrake cannot physically plug the nozzle when it's supposed to, so the piston just slams with full force against the cylinder head.

 

imma not even ask what's going on with the other piston.......

 

but yeah that's some pretty extreme taper. you might want a little edge chamfer to get the *ahem* protrusion to insert properly, but after that you want a nice tight fit between the (i swear to god this is proper engineering terminology) male and female components with plenty of stroke left (it's just getting worse isnt it) so build up the air cushion.

 

tbh i'd be more of a mind to go for a shit-ton of sorbo.

 

also inb4 all the kenneth williams impersonators: "ooh matron"

[Skara]

You mean the white bit?

Eggsdee  just leftover tape I'm not THAT desperate

 

new cylinder head I guess.

I was going to replace it anyway as it's aluminium and I utterly shanked it when unscrewing it the first time.

I'll try to source a flat one (they all have a small chamfer anyway) from a reputable manufacturer like Maple Leaf or Laylax.

In the meantime I will install the TDC, shorter barrel and dick around with various methods of internal suppression

[Adolf Hamster]

33 minutes ago, Skara said:

You mean the white bit?

Eggsdee  just leftover tape I'm not THAT desperate

 

wow i brain farted hard, i meant the one covered in white tape but i see that's the new one now.

[alxndrhll]

3 hours ago, Skara said:

 

Crap picture, but it should give you the idea.

I think that because of the tapered design the airbrake cannot physically plug the nozzle when it's supposed to, so the piston just slams with full force against the cylinder head.

 

@alxndrhll

Here it is  cylinder head, stock piston, weighted SCW from left to right.

 

sorry for the spam but it's bugging me.

 

It's hard to gauge precisely from here, but I agree that I doubt the airbrake is doing anything given the cylinder head design. Also looks like the ring on the head of the SCW piston does zero to cushion the impact due to the taper on the cylinder head. So it's just a straight metal on metal contact, hence the increase in sound over the stock one. Granted I know you're limited to 1J, but I shouldn't imagine that'll do either component much good!

It's weird because I don't recall the AA cylinder I put in my old VSR having the taper, but if it had that would certainly explain why the SCW piston was louder than anticipated. Granted I was coming from HPA, which makes everything else seem loud.