STG44 and MP40

Instead of cluttering up the “Recent Purchases” thread with more posts about it, I thought I’d start a separate one about the STG44. Looks like a few of us have one.
I posted in that thread the fps shots OOTB, and mentioned the lack of accuracy.
Jazzy’s suggestion of the LDT hopup won’t work. The outer barrel on this is just under 10mm ID, and those hopups are 11mm OD.

It’s a pity the gearbox didn’t have quick-change spring access, as you could swap springs by just taking off the stock to get at it.

So, tear down time.
Pretty simple to take apart (once you see someone else do it, that is :grinning:)
Well, the reason for the high fps is a 1.45 spring (135mm long)


It has a really good seal, even with the tappet fully extended forward.
Piston has one metal tooth at front, then the rest nylon.
Large delay chip on the sector. Looks like brass bushes (obviously not a tight fit in the shell) Shimmed.
Motor has decent torque. It’s not as good as a DOG motor, but I’ve seen a lot worse.


Barrel is 9.5 OD, 7.4 ID alloy. Approx 430mm long.

Anyway, I’ll try a smaller spring and see what happens.


That is a beefy spring :open_mouth: Interested to see the difference in spring change.

There’s slim hopups Rizer, sweethearts around to fit 9.5mm OD brl.


Nice breakdown and pics :+1:
I would definitely be changing that piston for something with a metal rack.
Metal gears on Nylon rack, with a 1.45 spring is not good for longevity :confused:


Don’t worry Bob, that spring isn’t staying :grinning:

I’ve tried a few springs now.
First was the old favourite - Ausgel 1.18 It didn’t like that one at all. Erratic and low fps.
Then a 1.25 wire (think it was an old airsoft spring) A little better, but still low fps.
Then a 1.28 Ausgel. Starting to get better, some results from that one -


Screenshot_2022-07-31-11-20-30-339_com.acetk.acesoft Screenshot_2022-07-31-11-20-40-101_com.acetk.acesoft


Screenshot_2022-07-31-11-20-50-412_com.acetk.acesoft Screenshot_2022-07-31-11-21-06-492_com.acetk.acesoft

But, you should be getting this fps or better from a 1.18, not a 1.28. As I said earlier, this blaster has a really good airseal, and a VE of approx 1.65, should be better results. Maybe that’s why they stuck that big-arse spring in it from factory :grinning:

As for hopups, I don’t think you will squeeze any slimline in between the inner and outer barrels.

I am waiting for someone else with one of these to post some results to see what they are getting. And also their opinions. This thread is not just for my STG, anyone with one can add their results, pics, comments. As we don’t have the sub-categories we had before.

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That’s odd :man_shrugging:

Wonder why has such large sector delay

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Noticed that delay chip myself and was thinking was a quick fix to convert tappet timing and travel from Asoft to larger Gels?
I wonder if the timing is correct and the nozzle is actually sealed before the piston is released :thinking:

With the original being a 1.45 spring, I would imagine that the AUSGEL 1.38 would be the immediate choice as a replacement :+1:


Could you easily swap the inner barrel out for a longer one that extends past the outer barrel, or is the inner barrel a weird diameter?

Alternatively that Clockwise 14mm thread would have adaptors online.

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Was your accuracy any better with those numbers? unchanged, better or?

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The barrel is normal 9.5 od. I have a 550mm s/s barrel coming that I’ll cut down to 470, which should give me enough poking out to get a hopuo on. But I really don’t want to damage that t-piece getting the stock one out. It’s a unique design.
Before I bought the blaster, I asked Ihobby if he was going to get spare parts for them. He said he was, but wasn’t sure at the time what they would be. I’ve asked him again, and I’m waiting for his reply.

Not sure what you mean by that. Adaptors for what?

I tried it again yesterday with some fresh Black Labels. The consistency is back, fps is slightly better. Maybe it likes fresh gels.

Single shot -

Screenshot_2022-08-01-13-32-58-271_com.acetk.acesoft Screenshot_2022-08-01-13-33-06-640_com.acetk.acesoft

Auto -

Screenshot_2022-08-01-15-08-10-105_com.acetk.acesoft Screenshot_2022-08-01-15-08-20-243_com.acetk.acesoft
Screenshot_2022-08-01-15-09-11-403_com.acetk.acesoft Screenshot_2022-08-01-15-09-34-318_com.acetk.acesoft

BUT, accuracy still no good :disappointed:
If it had decent accuracy, I’d be satisfied with those figures, and leave the 1.28 spring in it.

The quest continues :grin:

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I recall seeing an overview video that showed a 14mm clockwise thread under a cap at the front of the barrel. Though perhaps that was the MP40.

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No, it has the normal 14mm CCW end on the outer barrel.
It even comes with a hopup. Well made one too. Metal with 3 sets of different size tongues. And a birdcage flash hider that fits over the top of it.


The problem is the inner barrel ends approx 32mm inside the outer. So you have that space between the inner barrel and any hopup you screw on the end of the outer.

Just saw the post by @Haemoglobin about his HK hopup. Well, that must be what this one is.


If you can get the inner barrel out of the t-piece I’d probably end your replacement barrel flush with the outer and use that provided hopup.

@HelterSkelter ….
I think @BradleyPhillipsYT was alluding to the fact that the online reviews of the STG44 and MP40’s all showed that the flash hiders were Clockwise threaded onto the outer barrel, which is completely opposite to the standard CCW threads found on all other blasters.

Hence the need to find an adapter to convert the outer barrel to 14mm CCW standard to be able to run certain hopups/silencers/flash hiders/tracer units etc.

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Ok, now I see what he meant.
No, it’s definitely ccw. A DKJ10 screws on.
So much for online reviews :grin:

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How is the accuracy with the DK?

Same as the one it came with - terrible.
The problem is that gap between the end of the barrel and the start of the hopup.


Yeah, would certainly benefit from a longer inner barrel, and possibly barrel stabilisers along with a decent hop :+1:

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Both mention the Clockwise threaded flash hiders on both models.

Maybe these were early pre-production models :thinking:

But yours is definitely CCW threaded, so that’s great news for anyone looking to purchase one :+1: