Accuracey Problems with G&G RK-104

[JONNY-5]

Hey everybody,

 

Over the last month or so, I have been trying to tackle a minor accuracey problem that seems to have got the better of me, so I decided to join a forum and see if anyone can help.

 

The gun in question is a G&G top tech RK-104 which I have owned for about 7 months. It came stock with a stainless steel 6.03 tight bore barrel. I use Blaster 0.25 bbs.

 

The actual issue is that the bbs do not hold a consistenet grouping, and 1 in 5 bbs go completley off target. Sometimes the bbs vear left on every shot (I am holding the gun upright). When I say "off target" sometimes the bbs go left, sometimes they drop, sometimes they go too high, and sometimes they go right.

 

It started when I noticed a few small accuarcey problems, in which I believed were simply down to human error (e.g. wasn't holding the gun steady). I thought nothing of it.

 

When the problem gradually got worst, I cleaned and inspected the barrel, where I noticed that a small thread was hanging from bucking. I dissamsemled and replaced the bucking with another G&G green. It didnt fix the issue, and the new bucking actually developed the same small thread after 1 game.

 

I tried 2 different high caps and a mid cap to see if the performance would change, but it didn't.

 

I then did a compression test to make sure the air nozzle was sealing with the bucking. The compression was good.

 

Lastly, I ordered a RWA bucking to replace the second G&G bucking. I was delivered Madbull Shark bucking with fishbone nub, but I installed it anyway. This didn't fix the issue. I re-installed it twice just to confirm i hadn't botched it.

 

I also checked the barrel for visible scratches, which there were none.

 

The only thing that still puzzles me is that the air nozzle spins around if i twist it; is that meant to happen?

 

I am clueless on what the issue is, and it has beaten me. Hopefully you guys can help... Thanks very much in advance,

 

Jonathan

 

 

[RR01]

The air nozzle twisting is normal, so no problem there.

 

Accuracy with a standard airsoft rifle is never going to be perfect, but it really depends how far out the bb reaches before it starts to deviate. If it's at the end of its flight then that is probably normal, as they could be blown by air currents, but if within the first 20 yards then you have a problem with the setup. As you have tried different buckings then maybe it's time to try a flat hop. These are much easier to fit that an R hop or a G hop and won't take as much setting up. If all of that fails, try borrowing a different inner barrel to see if that makes a difference. If it does, buy a new inner.

[BrightCandle]

Accuracy is all about the air components, which from back to front is the Piston+head, Cylinder, Cylinder Head, Nozzle, Hop unit, bucking and barrel. So far you have assumed its in the bucking or barrel but it could very well just be wear and tear has produced an airleak in the gearbox itself and its putting out inconsistent air, it could also be the nozzle isn't quite in the right place and its damaging the bucking and perhaps sealing well into the bucking but not to the gearbox. So its time to crack open the gearbox and check the major parts including their airseal.

 

Where is the thread appearing on the bucking? A picture would be good but my guess is the lip based on what you have said so far.

[straffham]

From what you say it could be the air nozzle to hop rubber relationship is a tad too tight, so yes it seals well but with each shot its hitting the hop rubber more than it should. This could result in the hop rubber moving/compressing by a small amount each shot which may explain the shot to shot variations in accuracy and also the hop rubber damage you have seen.

 

I'm surprised it has a stainless steel barrel as stock but I'm not familiar with G&G AEGs to be honest. As suggested above try a different inner barrel, it could be its a tad too long at the hop end which would cause the problem mentioned above. Failing that I suspect the nozzle is slightly too long and may need a different V3 nozzle.

(I seem to remember Sitting Duck did a chart comparing nozzle lengths!)

[BrightCandle]

The Top techs have brass barrels not stainless steel and the finish one mine was so so at best.

[JONNY-5]

Thanks for the replies everyone,

 

BrightCandle - I did believe the barrel was brass as well, but when I took it out it is very obvious that it is not brass (silver colour), and the heavy weight led me to believe it was stainless steel. Also the thread appeared on the part of the bucking that meets the air nozzle.

 

So the general idea is that the air nozzle is not meeting the bucking correctly.

 

straffham, you mention that the barrel may be too long at the hop up end, but after 5 months of it working good how would that happen. I shall try a different barrel to see what happens.

 

I forgot to mention that the gun has the pneumatic blowback system. This means that there is a small chamber on top of then gearbox that fills up with air when the piston goes foward. Could an air leak in this chamber cause the problem?

 

Jonathan