[havokza]

So as some of you guys know I got a stock L96 and upgraded it doing the following.

All the DIY upgrades as per http://www.airsoftforum.com/board/Stock-MK96-Dummies-t172200.html except for the Barrel and hop part.

I also put in a Fijo Customs trigger (for those that want triggers go here http://www.fijocustom.com) it's an awesome trigger!

I replaced the stock Barrel and hop with the PDI HopUP unit as well as a 509mm Prometheus AEG barrel.
I added the PDI nub with a Prometheus soft bucking.

Now my issue is that I loaded some Madbull .40's and shot.
too little hop, adjusted the screws out some more.
Shot
too little hop.
Then when I adjusted the screws even more found that it now stops the nozzle ... so i removed the 2 screws completely thinking now I will have too much hop as I am assuming the less of the allen screws I see coming out the more hop. (Screws presses hopup arms up and makes the nub protrude less into the barrel.) So turn screws in less hp, turn screws out more hop.
Like so.

However even without those screws I don't have enough hop at all. BB's start curving down within 15-18 meters.
Like I said I'm using .40's and shooting +- 500fps.

I could build up the Hop arms with epoxy maybe.
Harder bucking? Prometheus Red or MadBull Red? Would that even make a difference?

Any advice?

 

[evilfish]

So you have the O ring and the spring pushing the arms down, yes? Usually the lack of hop is when the O-ring inside has been cut and the spring is left out. I think you have the "medium" arms in your unit. PDI makes short, medium and high hopup arms. You could try to create larger bucking.

 

[woogie]

How do you like the trigger?

I am thinking about getting one for my L96 and keeping the zero on the M24.

A review would be great man.

Yeah there are different syles of arms that can be used. Just make sure that if your cylinder doesn't go all the way into the rifle, don't force it. You don't want to mess up your nozzle.

I would look at getting a different set of arms. You should be able to get them for like $12 or so from any store. You will need the high arms I believe. This will give more length to the "fangs' that hold the nub on the bucking. Thus allowing for more hop up with less screw turning.

 

[fuzzywolly]

I had the same problem. No fear, fuzzy is here. : Its probably the bucking. I had it upside down and no matter how much I adjusted the screws, no hop with .4 bbs either. I got to the point where the screws would hit the cylinder head, which meant I could not push it all the way back in. Even with the screws out, no hop. Just rotate the bucking around. This should give you better results. You will find when you go to adjust the hop up now, it will not take much turning of the screws.

And you do not need the high arms for this one. I bought them and with the bucking upside down, I was having the same results. No hop, despite having the high arms. Also had the same results with the medium arms as well. However, woogie is right. The high arms are a good thing to have. It makes every little adjustment of the screws that more "sensitive" and less adjustment is needed for more hop of the bb to occur. Thus, resulting in more consistent shots.

However, you will not find any more hop with the high arms as long as your bucking is upside down. It causes some major down hop, no matter what you do (switch bbs, arms, etc.)

Overall: Upside down bucking= major down hop
Bucking in right position=one happy sniper

Here is what I used to help me. Written by Zulu on another forum:

Look inside the bucking (it's the hollow rubber cylinder). There will be one ridge that runs down the bucking lengthways, which slots into the long slit on your inner barrel (if it has multiple cuts, it's the most basic and longest one). Also, there's a horizontal ridge near the tapered end of the bucking that should rest over the breech of your barrel (the square hole in the end of it) when you slot the bucking onto the inner barrel. The breach should face UP (towards the side of the PDI chamber with the hop up arms). If you swivel the barrel 180 degrees you'll get severe hop DOWN.

 

[woogie]

They really need to mark the top of the barrel or something on these rifles. Would make things a lot easier.

I like to take some masking tape or something and mark where the "window" is. This will really help when you go to line things up inside the hop up chamber itself.

 

[fuzzywolly]

Agreed. I still get it wrong sometimes. And I have taken the rifle apart over 100 times

 

[woogie]

Yeah I really wish they would make a centering notch in them like the VSR does.

 

[havokza]

Thanks guys
Will def check that. makes sense Fuzzy!

Cause yeah I have the o-ring over. and the spring pressing down.
Could be an upside down bucking cause even with the screws completely out, still major down hop.
Will test it out.

As soon as I can get my rifle firing properly I will do a complete review of the custom trigger.

 

[bobgengeskahn]

i have had a simmilar issue with my aero chamber on my asr recently... i was just gong to try a bigger nub.... I have never seen an l96 specific unit in person, but from your diagram and your description the problem sounds the same although the design is a little different between the two... just my 2c