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Discussion Starter · #1 ·
Ok, so today a friend of my dad came over with his chrono. We chronoed my tanaka w/pcs bolt. The highest consistent fps we got was around 450fps(.2g). We thought it must be the seal in the bolt and the top of the mag that is causing the lack of power(rubber looks worn). What do you guys think? Are we correct? Also, I was using propane.
 

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Discussion Starter · #3 ·
I fideld with the PCS bolt. I had the valve as far open as I could have before the FPS started decreasing. Temp was a warm 70-75 degrees Fahrenheit. Upgradeds:
*G&G striker spring
*G&G bolt rubber
*King Arms VSR conversion chamber
*King Arms extended nozzle
*Creation Metal Part 91
*650mm Madbull Black Python II PSG-1 barrel
*Firefly Hard VSR-10 bucking

I intend to buy these parts to create a better air seal:

http://www.airsoftpost.com/product_info.php?products_id=32781
http://www.airsoftpost.com/product_info.php?products_id=33981
http://www.airsoftgi.com/product_info.php?products_id=6432

What do you think?
 

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Could the problem be that you're using a VSR bucking with an AEG barrel? I don't think you need the orings, as it would be cheaper to find a match at your local hardware store. The rubber set is probably what you need, and the springs will help as well. I'm not entirely sure as to what your problem is as I have a stock rubber set in my gun and it's shooting .4's over 450 on ~60 degree propane.
 

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Discussion Starter · #5 ·
We think the low fps is due to lack of airseal from mag to bolt. The O-rings, I thought, would improve the filling of the mag. Compared to my kwa mags, when filling, it sounds like gas is escaping. I highly doubt it has anything to do with the hop-up since it works supperbly.
 

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Discussion Starter · #7 ·
Even if it was the bucking I don't know how to take any of the hopup area apart. I tried taking of that huge golden lug nut thing, but it seemed glued on there! I would need a guide or something to take the hopup apart.
 

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Alright, I apologize for the lack of pics, but here goes:

1. Pull off outer barrel.
2. Unscrew knurled brass piece (not all the way, just far enough to drop the hop-up unit out of the receiver).
3. Make sure the bolt is back/out and then wiggle the entire hop-up unit out of the receiver. push the barrel towards where the back of the receiver would be. Be careful for two small pieces, one will come out of the side of the chamber when you pull it out of the chamber block, the other will fall out of the slot in the top.

You now have your barrel and bucking, do what you will from there.

A new knocker arm might be a good idea, as well as new impact plates.
 

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It could be several things. Weak knocker spring, mushed plate on the back of the mag. I could also be that are over filling your mags. Crummy seals which includes the valve seating to the bolt. You might want to take the valve out a little to see if your velocity increases. This also might include a weak spring supporting the brass rings that interfaces with he bolt.

Those are the correct plate but G&G has replacement parts that eliminate the need for that part altogether. I would suggest trying to simplify a overly complicated system. Any worn part could affect performance negatively but it should be very visible for you to loose 100+FPS. Have you tried chronoing the joules of heavier BBs. Usually gas gun can see some serious advantages with heavier ammo. 390FPS with .4g BBs is roughly 550FPS with .2g BBs.

http://www.airsoftoutletnw.net/index.php?page=shop.product_details&product_id=2741&flypage=flypage-ask.tpl&pop=0&option=com_virtuemart&Itemid=28
 

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Discussion Starter · #12 ·
No I didn't try chronoing with differnt weight ammo. How long should I be filling my mags? When I took the mag apart the Knocker Arm and Striker seemed to be in great condition. The lever that is part of the gas release system was really worn and so was the red rubber part on the underside of the bolt.
I just ordered the following:
G&G Valve Knocker: http://www.airsoftgi.com/product_info.php?products_id=6431
G&G Gas Route Connector Spring
G&G Rubber Air Seal Set
Replacement Magazine Valve Knocker:
http://www.airsoftpost.com/product_info.php?products_id=32033

The valve knockers are 2 different parts
This knocker goes in the trigger assembly right?:
http://www.airsoftgi.com/product_info.php?products_id=6431

Also, mateba you mentioned a G&G replacement part that would simplify stuff? What is it?

Edit: I think I just realized I bought an upgraded version and the normal version of the impact plate. Did I?
 

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Discussion Starter · #16 ·
So, how long should I charge my mag for? Because with my kwa mags I charge them for a long time, and I suppose I do that with my tanaka mag, but I don't know what is the right ammount.
 

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Discussion Starter · #18 ·
Well, I don't really know. I bought a bunch of the suggested pieces that were posted in this thread. When I chroned at a game I hit a staggering 518!
not really that high...anyways, that was after 6-7 attempts at chronoing
:(" title=":mad:" border="0"/> aggravated the hell out of me. I think the gas messed with the chrono, who knows. I just bought a nineball purple bucking because I figgured out that I had torn the bucking when dissasembling. Took the gun apart, looked like the previous owner had used this orange gunk stuff to make a better airseal on the bucking. He had also removed the lip on the firefly bucking that had been previously been installed(so whoever on here said that an airseal in the bucking area might have been the problem, was probably correct). So then I read the dremiling guide on ASF about putting that notch that circumferances the barrel, attempted it, and dremeled a hole in my inner barrel
:(" title=":mad:" border="0"/>
:(" title=":mad:" border="0"/>
:(" title=":mad:" border="0"/>
. So to sum it up; im saving for a new inner barrel....no tests for a while lol.
From,
toomanybbs a.k.a that idiot who drilled a hole in his barrel...
 

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Fair enough, I'll probably need to dremel a similar groove for my KJW M700, but about the low FPS issue, do you think it could be that the PCS bolt is open too far?
The striker spring guide/assembly will hit the PCS valve if it's open too far, I think it was over 85% (or thereabouts) and it'll obstruct the striker spring guide

Let us know how your setup goes when you get the parts sorted, thanks
 
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