Really Low Range

[Datawraith]

Hi.
I could really really really use some help.
Okay, so I have a JG G36C.
Stock, it fired 380 fps, too hot for indoors, so I had to do some tech work to detune it to 350 fps.
I bought an M90 spring and replaced the spring in the gearbox, and put it all together. (This actually took quite some work in changing the shape of the top of the spring because JG, being a China clone, had a retarded design and bent the spring into a hook to mount properly.)
Upon reassembling it, I noticed my hopup chamber was cracked, and I decided to see if I could repair it. So I ABS-cemented the chamber back together, when I realized I had lost the nub. After doing some research, I cut the end off a BIC pen and stuck that in as a temporary fix.
When I test-fired my rifle, the BB went about 10 feet, then dropped; I can't even begin to describe how wimpy it was.
That described how the rifle fired when it was adjusted to no hopup. As I dialed in the hopup, the rifle became more accurate and shot further and harder. However, this only worked for semi. No matter what I did with the hopup adjustment, full auto just dropped BBs out my barrel like there was no hop. I have to add that even on semi, it would still occasionally (every 10th BB or so), the BB would just drop out like there was no hop.
Can somebody give a possible reason for this? Is it because my hopup chamber was cracked and is maybe leaking or something? Or is it because my BIC nub sucks and I have to get a new legit one? Or maybe the M90 spring is just suck-ass wimpy? Or do I just suck at teching and seriously fcked something up?
Oh, and one more thing that's kind of unrelated; I contacted about 10 AV'ers about 2-4 months ago in both K-W and Markham (I'm a uni student), but not a single one replied. Could somebody please help with this too?
Many many thanks!
Datawraith

[Rommen]

I would try replacing the BIC nub with, you know, a real hop-up rubber and see how that works.

[AlexGPS]

First of all get a new hop up unit all together. Preferably a good make like madbull or promethius. Secondly you might have problems with your air nozzle not being able to retain air or should i say push air. It seems like you have a leak somewhere in the whole system. Might be a piston head nozzle or both. Preferably reopen the gun and dry fire it without the barrel on the gun. See if theres a leak somewhere. Maybe even relube everything and put it back together. First things first though get a new hop up unit. Glueing the piece back together isnt going to help much. Also check if the piston and so on that generate air are all in the propper place and all your o rings are propperly lubricated. If that doesnt work take it to a professional. Tell them what the problem is and theyll help you with it.

[Datawraith]

Thanks for the replies guys.
I guess I'll pop over to M1 when they open and get a new nub, before I get a whole new hopup assembly (JG uses a different design then most G36s; the chamber has a feed tube instead of the magwell, meaning that if I replace the hopup assembly with a standard assembly, I need a new magwell, which nobody seems to have in stock atm...).

[Cliffradical]

Providing us with pictures may also help. I'm having trouble arranging all of your troubles in my mind.
Spring bent into a hook? Hopup/ magwell different from other G36s?

This doesn't sound like any JG G36 I remember.

[lurkingknight]

he's talking about the marui style spring I imagine... the ones that integrate with the piston.... It's not a retarded china clone design. It's a retarded tokyo marui design.

Yeah, you don't bend that shit.. you replace it properly. You've just pooched your spring. Replace the piston head and piston body and by the sounds of it, a new 90 spring.

The JG g36 hop is proprietary, there's no aftermarket replacement as far as I know. But if it's back together properly, then do as the man says and put in a real nub. It's a hybrid.. looks sort of like a V2 hop with the feed tube but the top is more like the marui g36 hop. If it's completely fucked, you can convert it back to a marui style but you need the magwell from an ares/classic army/marui/old jg/cyma/src. Depending on the body pin configuration, (straight pin or threaded locking pin) you will need the correct magwell. The CA is a threaded pin. Not sure if the marui or src are or not as well. The ares is a straight pin.

Or you know...

Take it to someone that actually knows what they're doing.

[Datawraith]

lurkingknight's got it all correct.
Although, I don't see how if I just bend the first coil of the spring into the hook would screw it up too badly, unless you mean I can't use the spring in any other gun, which is fine as I have only this one. It is a retarded design though.
And yes, that describes the chamber perfectly. If I replace the whole assembly, I have to get a new magwell, and probably a new pin. Considering I use both the M4 magwell adapter as well as the G36 magwell, and that I'd have to get a new nub (would come with a bucking as well), on top of getting a new chamber... that's over $60... I have to spend a 1/3 of the gun's retail price to get it running properly again?! And that's if I do it myself, without paying a tech. And that doesn't factor in buying a new piston head and body and a 90 spring!
Hell, if I'd known this gun would be so much trouble, I would have just bought a KA M4....
Thanks though guys.

[Cliffradical]

AaaaAAAH... I get it. I read this wrong and had all kinds of things going every which-way.

But yes, bending or modifying a spring (with few exceptions) completely alters the way it bears and transfers load. It's borked.

Also, Airsoft is expensive. Building, modifying, and maintaining guns is expensive. That's why so many experienced players advocate buying in the upper-end and paying for tech work from the get-go. There's definitely a point where you 'save' money by spending it.
Your G36 isn't a total write-off, but it'll take a large amount of capital relative to it's initial cost to get it running properly, and your resale value these days will be what some people would consider offensively low.

Unless you factor upgrade/ repair costs into your purchase price (which often takes you into a higher bracket right there), "run it 'till it breaks" is the prime rule in buying clones.

[RainyEyes]

Originally Posted by Datawraith

lurkingknight's got it all correct.
Although, I don't see how if I just bend the first coil of the spring into the hook would screw it up too badly, unless you mean I can't use the spring in any other gun, which is fine as I have only this one. It is a retarded design though.
And yes, that describes the chamber perfectly. If I replace the whole assembly, I have to get a new magwell, and probably a new pin. Considering I use both the M4 magwell adapter as well as the G36 magwell, and that I'd have to get a new nub (would come with a bucking as well), on top of getting a new chamber... that's over $60... I have to spend a 1/3 of the gun's retail price to get it running properly again?! And that's if I do it myself, without paying a tech. And that doesn't factor in buying a new piston head and body and a 90 spring!
Hell, if I'd known this gun would be so much trouble, I would have just bought a KA M4....
Thanks though guys.

JG g36c owner here.

I've opened and re-opened my g36c so much, I know the ins and outs.

Firstly, the M90 spring might still shoot above 350 fps. Try the S90 modify spring.

Secondly, do not bend the spring into the piston head. Just leave it as is. The compression from the gearbox to the front of the gearbox where the piston strikes the cylinder head will keep any spring from moving out of place/bouncing. Why TM designed a hook into the piston head is beyond me.

Third, if you broke your hop-up, you should remember to be patient. To get the lower receiver out, you have to pull the hop-up forward all the way, and not let it snap back, which is probably what happened when you force it.

Fourth, AFAIK the battleaxe M4 to G36 magwell converter is not compatible with the JG G36c. There's misalignment that prevents it from working.

That being said, just get a new hop-up and try not to mess anything up. Bending the first coil of the spring into a piston NOT designed for that spring was foolhardy.

Consider it as tuition.

[Datawraith]

I don't think an M90 would shoot above 350 RainyEyes. The stock spring is either an M110 or M120 and that shot pretty consistently at 380, and everybody I've talked to said that the M90 should drop it below 350.

Guess the spring was a $12.00, 2-hour lesson. Good to know, and now I know better. This means I can just go out, get a new spring, and drop it into the current piston behind the metal piston head? (ie, keep everything the same, except don't bend the spring to attach to piston head, just drop it in)

The hopup chamber already had a hairline fracture in it when I first disassembled it. It was through no fault of mine. If I ABS-cemented it back together, it should be strong enough and airtight. I did an airseal test on it, and it seems like it isn't leaking.

The Battleaxe M4-G36 magwell adapter works fine with the JG G36C if you cut off the nozzle on the adapter. Of course, this means if you have a G36 with the standard hopup, you won't be able to use that magwell adapter anymore and have to get a new one.

Steep learning curve, but better to learn early on a cheapo gun then the eventual VFC right?

[Styrak]

Maybe you should give it to someone who knows what they're doing, to properly repair it with proper non-broken parts, instead of trying to fix it with glue and sticks.
Also an M90 spring will bring you to around 280-300fps, not 350fps.

[Datawraith]

I would Styrak, but it's so expensive to pay for a tech and it seems to me that being able to do a spring change is something anybody who owns an airsoft rifle should be able to do. And everywhere is closed because of the holidays, and I have a planned game this Friday, so I needed to detune it (figured it would be a good learning experience too). Glue and sticks might not look pretty, but hey, if it works (at least temporarily), great!

Yes, I was aware that an M90 would drop me quite a bit, as long as it was below 350, which you confirmed.

I guess I'll just run with a pistol on Friday before figuring out what the heck I'm gonna do to revive it. (Probably bring it to a gun doc)

[RainyEyes]

Originally Posted by Styrak

Maybe you should give it to someone who knows what they're doing, to properly repair it with proper non-broken parts, instead of trying to fix it with glue and sticks.
Also an M90 spring will bring you to around 280-300fps, not 350fps.

I can testify, and the tech that did my spring change at Toronto Airsoft can both testify that the M90 spring DID shoot 380 fps.

It was a 40 dollar tuition for myself to learn that only the modify S90 spring shoots at 350 fps +/- 1 fps with .20 grams in the JG G36c. That is my current setup with perfect compression and reasonable shimming.

It may be the result of some kind of manufacturing discrepancy where the M90 would result in 350~fps, but if you are confident in your gun, that is your decision and I respect that.

Having worked on V2 and now a V3 (both as a noob) and i can confidently say that changing the spring is NOT a beginner/novice task. There's a reason why the JG schematics do not include the inside workings of the gearbox in the manual, or why opening up a gearbox voids all warranty.