Nuprol Delta Ak21 Hop up Door Stuck ( Please Help )

[Sambo]

I have attached some images to my issue. just got the gun the other day and when I pulled back the lever to open up the Hop Up door, it will now not close. I've been in touch with the supplier and they are trying to say I need to press a button. I've tried to highlight the buttons that I can see. I am hoping that the case isn't that I have to take the gun apart to relieve any pressure that is on the door. I'm hoping it is me just being silly and not seeing the correct way to do it. I don't I know what the right name is for it but the lever that you pull back to open the Hop Up door pulls back but when I push It Forward it gets halfway in pulling the Hop Up door closed but after that it it loosens up and the Hop Up door stays half open. I hope my wording is ok for people to understand if anyone could help it would be massively appreciated thank you

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And the picture of my thumb is how hard I have been pressing button 4 for the record lol

 

[Adolf Hamster]

Button 4 is known as the bolt release, and in the real gun is used to drop the bolt after a mag change.

In some airsoft guns it does the same, a catch holds open the fake bolt and pressing the bolt release closes it, wether or not that's what your specific model does i couldnt say from the outside.

However what i reckon has happened here is one of 2 things:

1. The spring for the fake bolt has broken/slipped off meaning it wont close.

2. The fake bolt is wedged between the reciever and the gearbox, given how common this issue is if you pull it too far back, the lazy looking 2-tone job and nuprol's reputation for not particularly good quality i'd bet this is what's happened.

In either case you should be able to push the bolt forwards by hand, it might be a bit stiff. Hold the bolt release down (although not that hard lol) while your doing it just in case it catches.

You may need to split the reciever to get it unstuck.

However, i wouldnt worry too much, it's purely decorative and many folk dont even bother having a fake bolt at all so they can easily access the hop unit mid game.

 

[Rogerborg]

Yes, not a big deal, I've just binned my "bolt".

None of what you've highlighted looks anything like a release for it.  Sight unseen, I'm guessing that it's just stuck from the paint that they've spunked on it.

The good news is that M4/AR based platforms are a doddle to take apart. Just remove this pin and the upper receiver will slide forwards off the lower and give you access to the cover from the inside.

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[Sambo]

Button 4 is known as the bolt release, and in the real gun is used to drop the bolt after a mag change.

In some airsoft guns it does the same, a catch holds open the fake bolt and pressing the bolt release closes it, wether or not that's what your specific model does i couldnt say from the outside.

However what i reckon has happened here is one of 2 things:

1. The spring for the fake bolt has broken/slipped off meaning it wont close.

2. The fake bolt is wedged between the reciever and the gearbox, given how common this issue is if you pull it too far back, the lazy looking 2-tone job and nuprol's reputation for not particularly good quality i'd bet this is what's happened.

In either case you should be able to push the bolt forwards by hand, it might be a bit stiff. Hold the bolt release down (although not that hard lol) while your doing it just in case it catches.

You may need to split the reciever to get it unstuck.

However, i wouldnt worry too much, it's purely decorative and many folk dont even bother having a fake bolt at all so they can easily access the hop unit mid game.

Button 4. Thank you I was pressing it like mad and sliding the thing at the front of the gun forward and backwards and I must admit I did hear a noise that sounded like it released something but nothing seemed to be different. Now someone had confirmed it is something todo with that I'll try a bit harder. Thank you. 

Yes, not a big deal, I've just binned my "bolt".

None of what you've highlighted looks anything like a release for it.  Sight unseen, I'm guessing that it's just stuck from the paint that they've spunked on it.

The good news is that M4/AR based platforms are a doddle to take apart. Just remove this pin and the upper receiver will slide forwards off the lower and give you access to the cover from the inside.

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I've been trying to find videos of this gun but its nowhere to be seen. So if I take the pin out and slide one off the other. Does and spring come bouncing out or it is as easy as you say, take the pin out and slite one off the other. Really thank you for taking the time to circle the pin in my pictures. Thank you

 

[Enid_Puceflange]

Hi,

if you remove the pin and slide your blue upper forward & away from the lower slowly, the spring may swing out but I doubt it will fall away completely 

it is a small spring (similar in size to one in a “click” ball pen) with little hoops or hooks on either end

Either the upper section or bolt cover will have an empty hook for the spring to attach 

pop it on and re assemble

May I suggest a bit of white spirit or similar, and remove the blue paint on the bolt cover

That should stop it sticking again and needing the same job done , it should have been covered when the store painted it two tone for you.

 

[Rogerborg]

I've been trying to find videos of this gun but its nowhere to be seen. So if I take the pin out and slide one off the other. Does and spring come bouncing out or it is as easy as you say, take the pin out and slite one off the other.

Shouldn't be anything complicated. Your inner barrel and hop unit are inside the top receiver / outer barrel, your gearbox is secure in the lower receiver.  The only thing to keep an eye on is that the hop unit may have a small compression spring on the front of it to push it back against the gearbox and nozzle, so just keep an eye on that (or it may not and the spring will be around the barrel instead).

As Enid notes, there will be a spring for the bolt cover in there, but it shouldn't just escape unless you've very unlucky, and that's what you're in there to sort out.

These really are very simple to take apart, I'd just get right in there and see what's what.  Just pin out, pull apart, bish bosh, you're an airsoft tech.

 

[Sambo]

Hi,

if you remove the pin and slide your blue upper forward & away from the lower slowly, the spring may swing out but I doubt it will fall away completely 

it is a small spring (similar in size to one in a “click” ball pen) with little hoops or hooks on either end

Either the upper section or bolt cover will have an empty hook for the spring to attach 

pop it on and re assemble

May I suggest a bit of white spirit or similar, and remove the blue paint on the bolt cover

That should stop it sticking again and needing the same job done , it should have been covered when the store painted it two tone for you.

Thank you for your time.

I cant find a video of this gun been taken apart but I'm really thinking of giving it a go as I cant send it back because it will cost a bomb and the shop is well too far away. There a local airsoft shop in Sheffield which is a lot closer so I'm tempted to take it there and to see if they wont mind helping even tho I didnt buy it off them. But everyone is saying it's easy to take apart so I might give it a go. Really really thank you.

And wood white spirits get the blue off all the gun do you know?

Shouldn't be anything complicated. Your inner barrel and hop unit are inside the top receiver / outer barrel, your gearbox is secure in the lower receiver.  The only thing to keep an eye on is that the hop unit may have a small compression spring on the front of it to push it back against the gearbox and nozzle, so just keep an eye on that (or it may not and the spring will be around the barrel instead).

As Enid notes, there will be a spring for the bolt cover in there, but it shouldn't just escape unless you've very unlucky, and that's what you're in there to sort out.

These really are very simple to take apart, I'd just get right in there and see what's what.  Just pin out, pull apart, bish bosh, you're an airsoft tech.

I love how easy you make it sound. I've always wanted to play airsoft but struggle with anxiety so I'm trying to build my self up to go so that why I bought a gun lol need a lot more other stuff but I cant stop watching people on YouTube playing it and it look mint!!

As soon as I get home I think I'm gonna try take it apart. I love the bish Bosh your now an airsoft technician ???

Thank you

 

[Enid_Puceflange]

Hi Sambo

before you open the floodgates of legalities and rules etc

I meant only remove the blue paint from the sticking bolt cover and the surrounding area , don’t go removing the blue from your entire  pewpew !
I think it’s the blue paint sticking things together that has initially caused your problem. 

 It taking the gun apart, is quite as simple as we have said ?

Should be a quick & easy fix for you despite your hesitations. 

 

[Sambo]

I would just like to say absolute massive thank you to you all!!!!! I wouldn't have sorted it out without you all!!!!! I pressed the button 4 ( kinda hard ) and slid the thing forward at the front of the gun and I hurd the smallest little click and it was more closed then it has ever been so I just helped it along a bit with my finger and a little wiggle and it now closed. 

I honestly cant thank you all enough!!!!!!

THANK YOU!!!! ???????????

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[Rogerborg]

Great stuff!  I strongly suspect it is just gummed up with paint rather than being an inherent problem with the gun.  If it does stick again, I'd encourage you to pop that pin, split the gun and strip the paint off the bolt cover - you'll be amazed how quick and easy it is.

Depending what they've painted it with, white spirit might work, or isopropyl alcohol. I wouldn't rush to use anything harsher than that on plastic.  If the cover itself is metal, go to town on it.