Tuning - KWA M4

[bao_pay]

Bought a KWA M4 rifle last year and finally shot it up at the cottage this weekend. Shot a few hicap clips and loved the performance at close range tearing up pop can and under 50 ft, but after that, the BB's take a sharp slice to the right.

In reading about hop up, the way the BB ascends or decends can be adjusted with the hop up, but is there any way to adjust left to right slicing?

Thanks for any help you guys can provide!

[JonsM4]

What kind of BB's you using? Weight?

[Deathfox]

bb's could be of bad quality, also the bb's could be too light for the gun. Try using .25g. After all that and your still having issues, then its the hop-up bucking. Could be not 100% in the right spot (happened to me)

[bao_pay]

Using .25 SIIS sekito

Says product of japan

[bao_pay]

What does the bucking do and is it easy to fix? I'm a newb to all this still.

[Styrak]

You would have to take out the inner barrel + hopup and check the alignment.

[lurkingknight]

does the slice get better or worse when you adjust hop? If it's being affected by hopup adjustment, then the barrel and hopup bucking are out of alignment. It could still be they are out of alignment even without adjusting hop but just slightly. Straight off or does it curve increasingly? If its actually arcing, your hopup rubber is probably to blame... it's not aligned properly.

Did you swab the barrel out with some clean cloth and the unjamming rod? I have a pistol that shoots off center when the inner barrel is dirty.

Also check if your sights are not out of adjustment in windage... Maybe the rear sight got tweaked and The gun is shooting straight, and you are just aiming left.

If it's a really consistent vector off to the right it should be easier to find lol.

[Deathfox]

Originally Posted by bao_pay

What does the bucking do and is it easy to fix? I'm a newb to all this still.

To put it simply. It's basically a rubber (silicon) sleeve that goes around the inner-barrel, it forms a "lip" at the end of the barrel, which, if isnt in the right place will do all sorts of funny things.

but it just dawned on me. you had bought the gun some time before using it, which means that bucking needs to get lubed. Just put 1 drop of silicon oil in the hop-up (where bb's feed into the gun). At first it will shoot funny. But after 50-100 rounds it will fix.

Make sure the inner-barrel is clean. Also if that doesnt work. I would suggest getting a even heavier bb than .25g. I had the same issue where it would always veer to the right. I even tryed to replace the bucking, and did the same thing. But the second i put .28g bb's in it. It shot like a DREAM. It depends on the FPS your gun is shooting and the weight of bb's you use. Do you know the FPS with you rifle?

[Styrak]

Originally Posted by Deathfox

but it just dawned on me. you had bought the gun some time before using it, which means that bucking needs to get lubed. Just put 1 drop of silicon oil in the hop-up (where bb's feed into the gun). At first it will shoot funny. But after 50-100 rounds it will fix.

Lubing the inside of a hopup or hopup rubber is not a great idea.

[Deathfox]

Originally Posted by Styrak

Lubing the inside of a hopup or hopup rubber is not a great idea.

i have to disagree. The silicon bucking is like any other rubber and doesnt like to get too dry, if it does it can start to crack, plus the second you clean the barrel all excess lube is gone. Putting 1 drop of silicon oil to keep the bucking moist wont hurt anything, its just when you put more.
I have done this quite a bit, and fixes the issue almost everytime, never hurt anything.
But i will admit there is better ways to lubing the bucking.... Taking the bucking right out and lubing would be better than doing it while still in the hop-up.

[dodgetheram]

I learned from a few friends thats its not bad to pull your bucking off and let it soak it silicone oil every once in a while, just making sure to wipe it off completely before puting the bucking and sleave back on. Just like any other rubber it will dry out and crack over time, just like stated before. However when I was new (I guess I still kinda am ) I sprayed a bunch silicone spray into the hop up, I thought my aeg was bunk for about a week, then I pulled it apart to find my hop up nearly dripping with oil, so after a quick clean and rebuild, it shot wonderfuly!

[lurkingknight]

lol... at 3-5$ a shot, I just replace the damn thing rather than have my range messed up for half a game.

[karl_azytzeen]

Take a look there
http://kwausa.com/forums/index.php?showtopic=8732&st=0

[DavidoftheDoell]

KWA staff do not recommend oiling the hop up or the inner barrel. Check out their forums for the maintenance thread. KWA knows their own product best.

I am having a similar problem and I will try looking at the alignment. My gun is very new so there's no way the rubber is worn out already. I'm using a lower than stock spring so I'm wondering if that is affecting performance.

[karl_azytzeen]

My rubber comes back un bad condition (ardened). Changign it for madbull black and ultrafire Hnub im getting 220ft+ range (65meter) You can look for al the tunes in the post linked....

And:
-Bucking, hop chamber and magazine should be as clean as possible, to provide the best contact between ball and bucking.
-Clean the barrel dry or with oil will provide different results, sometimes good sometimes bad, depends on the combination of your bb, bucking, barrel...