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JG Bar 10 weighted piston (stock)

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4K views 18 replies 4 participants last post by  sumatra  
#1 ·
I'm looking for some tips on weighted pistons. The one I have on my JG Bar 10 is the stock plastic one. I've tried weighting it, but I didn't get good results. I'm pretty sure I did something wrong.
 
#2 ·
You can’t just add weight or slap a weighted piston in and have good results. There are many variables that come into play such as;

Barrel length
Barrel bore
Spring
Piston length
Hopup components

Those are just basic variables off the top of my head. You will read and see people post things like;

“short barrel heavy piston is great for joule creep”.

I’m fully convinced that the joule creep hype is SO exaggerated. Joule creep happens with heavier bbs, that’s old news. But the REAL joule creep is bringing the .20 and heavy weight bb fps outputs closet together. The results are there, but not as insane as people say. Can you gain power by adding weight? YES. But it isn’t always going to be with your cliche heavy piston and short barrel.

Also, the only reason you’d want actual creep is to cheat the chrono. Which is a dick move, and even if your gun shoots within chrono limits with a .20, but more than your average sniper rifle with a .48 for example; the increase in power isn’t that much so it’s not like you have this huge advantage.

Sorry for the long rant. Especially since you didn’t even mention what you actually wanted to add the weight for. But I think piston weight is more for tuning fps down and adjusting your gun rather than jOuLe CrEeP.
 
#3 ·
Blind Sniper said:
You can't just add weight or slap a weighted piston in and have good results. There are many variables that come into play such as;

Barrel length
Barrel bore
Spring
Piston length
Hopup components

Those are just basic variables off the top of my head. You will read and see people post things like;

"short barrel heavy piston is great for joule creep".

I'm fully convinced that the joule creep hype is SO exaggerated. Joule creep happens with heavier bbs, that's old news. But the REAL joule creep is bringing the .20 and heavy weight bb fps outputs closet together. The results are there, but not as insane as people say. Can you gain power by adding weight? YES. But it isn't always going to be with your cliche heavy piston and short barrel.

Also, the only reason you'd want actual creep is to cheat the chrono. Which is a dick move, and even if your gun shoots within chrono limits with a .20, but more than your average sniper rifle with a .48 for example; the increase in power isn't that much so it's not like you have this huge advantage.

Sorry for the long rant. Especially since you didn't even mention what you actually wanted to add the weight for. But I think piston weight is more for tuning fps down and adjusting your gun rather than jOuLe CrEeP.
Click to expand...
Thank you for the rant, I will keep it in mind from now on.
My JG is still stock (for the most part) and with 0.4's shoots at 0.8 J. I'd like to increase the power a bit because as far as I've heard I'll get a little more distance out of the gun and It'll be quieter. I've already done all the DIY I can (except TDC, for now). I don't currently have the finances to get decent upgrade parts, so I've just popped in a new autobot 75 bucking and I'm waiting for a ML hopup lever.
With all that being said I'd like to gain as much as I can from DIY upgrades and that also includes every little bit of knowledge and experience.

P.S. Its the JG Bar10 Pro, not the short version.
 
#4 ·
Awesome! You can boost the performance a tad even with it stock. Teflon seal with that barrel length will give you decent numbers for a stock spring. I’d definitely try and get a 90° trigger though, then you will have no worries with a bigger spring. Another cheap easy mod would be a spring spacer. If you take some measurements, you can order needle bearings from amazon and they work great! Can’t get spacers too thick though or the sear won’t latch!! Good luck on your build!!
 
#5 ·
Blind Sniper said:
Awesome! You can boost the performance a tad even with it stock. Teflon seal with that barrel length will give you decent numbers for a stock spring. I'd definitely try and get a 90° trigger though, then you will have no worries with a bigger spring. Another cheap easy mod would be a spring spacer. If you take some measurements, you can order needle bearings from amazon and they work great! Can't get spacers too thick though or the sear won't latch!! Good luck on your build!!
Click to expand...
Thank you very much, I hadn't heard about spring spacers until now and will look into it.
I've already improved the seal as much as I can and I'll try to get enough $ to get a 0-trigger set + compatible cylinder w/ internals.
Also could you perhaps point me to a reliable source for the piston weighting? Having a solid foundation would save me some time in testing.
 
#6 ·
There is TONS of info on here. For weight the easiest route that makes the most sense if to get a roll of solder, like for a soldering iron. Wrap it around the piston and then add some electrical tape. If you want to get fancy, and you have more materials & tools; I have a DIY on my channel for how to make a weighted piston. HOWEVER my method is best for pistons where the sear end comes off. Or you’d have to make a sleeve and cut it in half to fit piston. Many options.

Other options, speaking of, you can just buy and EdGi SAP. Amazing quality, many adjustments....but high price tag.


Hope that helped!!
 
#7 · (Edited)
Quick update.
The stock plastic piston weights at almost 20g, I increased it to 25 and it got a bit quieter, but I lost some compression, max distance stayed pretty much the same I believe or it may be 5m shorter.
I then tried 30g and there is almost no change in sound, however I lost another 10m maybe.
I'm not sure why the compression got worse, maybe the small leaks I had before (it was almost perfect...almost) just got worse now or maybe there is a new leak. It sounds like it coming from the bottom part of the cylinder where you can see the spring and piston.

Thoughts?
 
#8 ·
If you are experiencing power loss when adding weight, it's obviously not meant to be there lol.
Here are some tips to increase power for next to nothing.
#1 buy some metal washers or rings that are 7X10mm for spring spacers and stack some on your spring guide.
Too many will result in your piston not catching.

#2 if your piston has a rod coming out of the front(airbrake), cut 1/2 of it off as it helps with sound but reduces power.
It's still good to have some left though, as it would be noticably loud otherwise.

#3 wrap PTFE(Teflon) tape around the threading on your cylinder head to improve seal.

#4 wrap 2-4 layers or PTFE tape around the last 5mm of your bucking when installed on your barrel.
This will add material for the hop chamber to squish down on, which should improve air seal.
The end of the bucking that's on the barrel btw.

#5 put your cylinder head in a drill and use a shitty knife, file, or sandpaper to make the back of the cylinder head look like a funnel shape.

From here on is stuff that will cost some money.

#6 buy an Action Army hop chamber

#7 buy a tighter barrel

#8 buy a stronger spring

I would suggest that you try all of the free or almost free mods, and then see how you like your gun.
I would also highly suggest that you read this completely.
https://www.airsoftsniperforum.com/?utm_source=a2hs#/topics/6075

Hopefully this helped, as these mods certainly helped me around b3 years ago.
 
#9 · (Edited)
SiliconeSword said:
Hopefully this helped, as these mods certainly helped me around b3 years ago.
Click to expand...
I can't really measure if there is any loss in power, don't have a chrono on me. However I removed all the weight, but still have more air leaking than I did previously, so I reckon the loss of power is because of that. I have no clue as to why I suddenly lost that almost perfect compression.
I've done most of the stuff you have suggested. Will test out the nozzle shaping after I upgrade so I can do a test on the stock one in case I f up.

P.S. The link opens the home page.
 
#12 ·
I've read that thread a long time ago.
I will definitely try out the spring spacer.
As for the compression, I believe the O-ring is the problem, the piston doesn't completely stop, but continues moving really slowly. I've put a lot of ptfe tape under the ring and that helps out a ton.
Right now however I removed all the weight from the piston but somehow when I fire the piston does not slam the way it used to. Its as quiet as a whisper and naturally of course BBs dont exit the barrel and stay jammed up to 2 or 3. I will address this issue tomorrow however.
 
#15 ·
Yeah, you want the O-ring to be loose on the piston and you want the O-ring to be firm enough in the cylinder.
Obviously, too tight in the cylinder is bad, that's what the PTFE you have is doing, it's providing too much friction for the piston to speed up.
 
#14 ·
I would not add weight to the plastic piston. With the extra weight the piston will need a bigger spring and the plastic piston will start slam firing in a week or so. They are a pain in the backside. You really need a new trigger and piston before you can make big headway with this rifle.
 
#16 · (Edited)
After today's tests I figured that its not really a good idea to put weight on a plastic piston.
I'm planning on upgrading to a full zero trigger set from airsoftpro https://airsoftpro.cz/en/gun-parts-...or-vsr-and-mb02-3-7-9.../zero-upgrade-set-pro-pusky-vsr-a-kopie-ver.-4.1-detail
I've heard its pretty good, but if someone can share an opinion I would appreciate it.

EDIT:
Airsoftpro also offers PDI trigger set https://airsoftpro.cz/en/gun-parts-...r-vsr-and-mb02-3-7-9.../cnc-spoustovy-mechanismus-pro-tokyo-marui-vsr-10-detail

ML set https://airsoftpro.cz/en/gun-parts-...r-and-mb02-3-7-9.../kompletni-upgrade-valec-a-zachyt-pistu-pro-marui-vsr-detail
 
#18 ·
PDI = used to be the best, now it's decent but expensive

Maple Leaf = not much experience, probably fine

Action Army = easy to find, but not too great

Laylax = same as Action Army, but more expensive and slightly worse

JJairsoft = bad, don't get it

Fijo Custom = probably good, but shipping from Brazil is probably slow, sketchy, and expensive

Springer Custom Works = really good

AirsoftPro = quite good, especially for the price

Bulltrigger = really good, if not better than Springer Custom Works as it in theory gives you an FPS boost

Iron Trigger from Aitsoftguns Europe = probably about the same as AirsoftPro

Angel Custom = fine, but not at all worth the price

As for the ESC Works 45° to 90° sears, perfectly fine for 1J like he and his customers use them for, but no more

So there, hopefully this helps you along.
I myself am gonna get a Bulltrigger in the future as well as a PDI Bore Up cylinder, but that will be when I have a better job and so on.
For now I'm happy with my Wolverine BOLT.
 
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