"VFC" Scar L troubleshoot - ideas?

[Aragrev7]

Can't seem to post in Gun doctor. Most likely need more posts...
If this can be moved would be helpful!

Bought this "VFC" SCAR L from Hughes:
http://www.airsoftcanada.com/showthread.php?t=167022
-11.1 lipo (to be replaced with 7.4).
-.25 match grade BBs from evike (work perfectly on buddy's brand new VFC scar L)
-70* bucking
-flat hop mod

Among several issues of mags being jammed, or pieces missing, My major problem is #3, which takes priority.

It's been running okay, but definitely giving me trouble.

1. It miss-feeds consistently. I noticed the nozzle is visible thru the feeding tube, which makes me think that might be preventing BBs from getting in properly. For example, to shoot my first BB it dry fires once then as the nozzle slides back and resets it allows on in and then it works.

2. Also jams due to hop up easily. The flat hop mod is very aggressive. It takes minute adjustments that put it from no hop to jammed. BBs start doubling up and falling out the barrel. I recognize this right away and stop shooting of course. I noticed it also takes quite a bit of force, respectively, to push the BB through the bucking manually. My guess is this can be fixed with a new bucking and maybe reduced flat hop height.

3. **** After sitting in the cold (trunk for a few hours), my gun seems to refuse to fires. The trigger pulls and no engagement whatsoever. It has made a solid shot 2 times. But took 1/20.
Have checked:
-battery: tried 11.1 lipo (voltage check each cell), 9.6 nimh,
-continuity in wiring thru stock
-continuity in mechanism (semi on, trigger pulled & test)
-wire leads on motor at bottom of pistol grip look good.
-direct feed of batter to back of mechanism provided second partial shot. Then nothing.

Any help would be appreciated as I have a big event tomorrow with the guys and gals.

Thanks!!

[pestobanana]

1. That is normal on AEGs

2. Flat hops are sensitive to adjust. If it is jamming, either the flat hop was not installed properly or you are not adjusting it properly. Alternative hop up setups are sometimes harder to install in VFC SCARs because the hop up unit is a very tight fit.

3. Do you have to pull the trigger very hard to get a shot? If so your contacts are burning out and you need to squeeze the contacts closer together and probably install a MOSFET.

[Danke]

My VFC SCAR was very sensitive to hopup rubber/nub. Too hard or too much and it would jam till it had a few BBs in the chamber and the bloop four out at once. I found the Guarder clear or the black Systema with the respective nubs worked best.

I also found it to be very tough on batteries. My only guess on that is that the hidden contact>hinge/gearbox>lower connections had a ton of resistance. I got rid of the fuse and ran a 9.9v 20C 1400mah LIFE Battery that would fit in the stock. That would run for a days worth of gaming.

[Aragrev7]

Thank you for the very quick reply!

1. I brought it up bc my buddy's VFC does not sit so, but maybe that is reducing his seal a bit.

2. It's basically all or none the way it works. Even with the smallest of adjustments, as well as side spin (shot within a gym). The flat hop I made for my G36 functions better. Not a huge deal for now.

3. Problem solved! The Springer terminals at the back of the gear box were jammed with shredded heat shrink. This prevented them from springing out far enough to consistently touch the stock contacts. Cleaned up and works great!

[Wrath144]

No trademarks, not VFC. Probably DBoys, as that's the only Scar I've seen without some kind of trademarks.

[ThunderCactus]

The air nozzles position depends entirely where the sector gear stops. In full auto it can be random, in semi it can be in a different place on every gun. The only thing that matters is that it visibly goes back and forth every shot.

Misfeeding can be due to the rubber, but also check the tappet plate.
Sounds like the flat hop was done wrong, or they didn't use a soft enough nub for it. Flat hops especially should never straight up jam a gun when you overhop a little bit, they're designed to spread the contact over double the length, so you should be able to get much more overhop with a flat hop than a conventional rubber.
I'd also argue the 70* rubber is too hard for a flat rubber. There's less wear on them to begin with by design, but you also need a softer material to impart more grip over the length of it.

[pestobanana]

Originally Posted by Wrath144

No trademarks, not VFC. Probably DBoys, as that's the only Scar I've seen without some kind of trademarks.

Nope. That looks like VFC to me. DBoys colouring is different, their gas block is black.

VFC SCARs have different trades depending on when they were made. They started off with full trades, then ran into legal issues and made them without trades. Now they have acquired licensing but have "Made in Taiwan" written beside the trades.

[pestobanana]

Its sometimes hard to determine if the flat hop hasn't been installed properly or if the user simply isn't adjusting it properly. I've installed many flat hops where the issue was simply user error.

Its possible that it hasn't been installed properly, since his original ad says

"The Flat hop is brand new and needs a little working in, but otherwise no issues internally.
fps variance +/-2 fps"

Originally Posted by ThunderCactus

The air nozzles position depends entirely where the sector gear stops. In full auto it can be random, in semi it can be in a different place on every gun. The only thing that matters is that it visibly goes back and forth every shot.

Misfeeding can be due to the rubber, but also check the tappet plate.
Sounds like the flat hop was done wrong, or they didn't use a soft enough nub for it. Flat hops especially should never straight up jam a gun when you overhop a little bit, they're designed to spread the contact over double the length, so you should be able to get much more overhop with a flat hop than a conventional rubber.
I'd also argue the 70* rubber is too hard for a flat rubber. There's less wear on them to begin with by design, but you also need a softer material to impart more grip over the length of it.

[ThunderCactus]

Needs working in? Yeah definitely wasn't done right.
I've never done a hop mod that still needed "working in" when it was finished.

[Rabbit]

Why do plastic hop up units still exist. Seriously.

Vfc and dboys take it to a whole new level of hershey squirts with these clear units in scars.

Theres a good video on youtube of a tech explaining the hop up arm on the vfc scar units is completely off resulting in uneven hop and jams.

[pestobanana]

Originally Posted by Rabbit

Why do plastic hop up units still exist. Seriously.

Vfc and dboys take it to a whole new level of hershey squirts with these clear units in scars.

Theres a good video on youtube of a tech explaining the hop up arm on the vfc scar units is completely off resulting in uneven hop and jams.

No. That video you showed me was an improperly installed hop up. I've never experienced the issue with my scar.

[Danke]

The clear hop in the VFC SCAR is fine. Setup properly with a soft rubber it equals or outshoots one piece metal ones.

The real problem is people with no patience and no mechanical aptitude trying to shoot four hundred feet by buying stuff, and then giving up and selling it to an unsuspecting new player when it doesn't work out of the box.

[ThunderCactus]

There is such a thing as "over-tweaking"

[ThunderCactus]

So I heard from the original gundoc of this gun, apparently Aragrev had taken the gun apart upon arrival. Is that true? Was it taken apart for inspection? Did you take the hop unit apart?

[Aragrev7]

This is incorrect. I did not take the gun apart upon arrival. I bought it in the AM and went directly out to the field to play. Owner said he would have it set up and ready to go for my day.
Performance did not turn out the way it was described too. Mag pull grip was not provided as described (gave an strike industries grip instead).
Additionally, 2 mags were jammed, and when notified, replied with "didn't realize" even though they were marked with big "X's". Missing hop up adjustment tool (just use my fingers)etc etc.
Sure the gun shot. Having dead mags didn't help the experience of course. The gun still jams or double feeds consistently.
The hop up is not very consistent, meaning BB fired: 1. Drops at 70ft; 2. Straight-ish flight passed; 3. Similar straight flight; 4. Too much hop BB climbs erratically/spirals at 70ft; 5. Straight or drops. The resulting spread is larger than my friend. Wind does play an affect, shots downwind go further with the same effect.
I have a Guarder 50* & nub on order.