This mod is for L96 users. APS2 users might be able to do this mod, but I personally don't know as I've never owned one.
Prologue
I actually thought up this mod back when I was a sophomore in high school, 3-ish years ago. I originally wrote a guide for it as well, but looking back on it, I feel like the guide wasn't written very well, and my opinions have slightly changed since then.
Link to the old guide (on ASR) (keep in mind, it's kind of... sporadic): http://www.airsoftretreat.com/forums/index.php?topic=94220
The Problem
One of the main problems with the L96 platform is that the hop up chamber is able to rotate left and right within the gun. This is a problem because, if the hop up chamber is able to rotate, then the direction of hop applied will not be consistent.
Any little bump along the way can cause the chamber to change it's position and rotate, causing unwanted sidespin. The only thing that prevents rotation is a tiny grub screw within the receiver, which is utterly useless. In fact, the original Maruzen doesn't even have the grub screw, so it wiggles freely.
The reason the hop up chamber can rotate is because of the mag-catch. It is directly attached to the hop up chamber, and has lots of room to wiggle within the stock, thus allowing the hop up chamber to wiggle and rotate.
This is the mag catch.
Whether you have a stock hop up chamber, a PDI, an HP, or whatever, you will still have this problem, since they all use the stock mag-catch.
Side note, also, the screw that attaches the mag-catch to the hop up chamber MUST be screwed tight, or else the hop up chamber can wiggle even more.
The Solution
The way to prevent the mag catch from wiggling is to simply fill in the "wiggle room," thus fixating the mag catch in place. In more familiar words, the mag catch must be "shimmed."
There are lots of ways to shim the mag catch. You can use some tape, since it's quick and easy. More durable tape is more preferable, or you can use an epoxy or JB Weld if you want it to be even more durable.
How to Do this Mod
Quite simple, all you do is apply tape/epoxy on the sides of the mag catch until the "wiggle room" is filled. It's all trial-and-error. If you don't put enough, the mag catch will still wiggle. If you put too much, on the sides, the mag catch won't fit.
You shouldn't have to screw and unscrew the mag catch each time you do your trial-and-error.
Epoxy users will find it easier just to put a nice wad of epoxy on the mag catch, and then sanding/filing down the excess until there is a perfect fit.
MS Paint Skills
The most important part to place your tape/epoxy is at the portion closest to the hop up chamber. If you miss this spot, the hop up chamber will continue to wiggle.
Here's mine. I used JB Weld.
Notice how I only put the JB Weld at the top of the mag catch, as I said before. Pretty? No. Effective? I have no wiggling whatsoever.
Prologue
I actually thought up this mod back when I was a sophomore in high school, 3-ish years ago. I originally wrote a guide for it as well, but looking back on it, I feel like the guide wasn't written very well, and my opinions have slightly changed since then.
Link to the old guide (on ASR) (keep in mind, it's kind of... sporadic): http://www.airsoftretreat.com/forums/index.php?topic=94220
The Problem
One of the main problems with the L96 platform is that the hop up chamber is able to rotate left and right within the gun. This is a problem because, if the hop up chamber is able to rotate, then the direction of hop applied will not be consistent.
Any little bump along the way can cause the chamber to change it's position and rotate, causing unwanted sidespin. The only thing that prevents rotation is a tiny grub screw within the receiver, which is utterly useless. In fact, the original Maruzen doesn't even have the grub screw, so it wiggles freely.
The reason the hop up chamber can rotate is because of the mag-catch. It is directly attached to the hop up chamber, and has lots of room to wiggle within the stock, thus allowing the hop up chamber to wiggle and rotate.
This is the mag catch.
Whether you have a stock hop up chamber, a PDI, an HP, or whatever, you will still have this problem, since they all use the stock mag-catch.
Side note, also, the screw that attaches the mag-catch to the hop up chamber MUST be screwed tight, or else the hop up chamber can wiggle even more.
The Solution
The way to prevent the mag catch from wiggling is to simply fill in the "wiggle room," thus fixating the mag catch in place. In more familiar words, the mag catch must be "shimmed."
There are lots of ways to shim the mag catch. You can use some tape, since it's quick and easy. More durable tape is more preferable, or you can use an epoxy or JB Weld if you want it to be even more durable.
How to Do this Mod
Quite simple, all you do is apply tape/epoxy on the sides of the mag catch until the "wiggle room" is filled. It's all trial-and-error. If you don't put enough, the mag catch will still wiggle. If you put too much, on the sides, the mag catch won't fit.
You shouldn't have to screw and unscrew the mag catch each time you do your trial-and-error.
Epoxy users will find it easier just to put a nice wad of epoxy on the mag catch, and then sanding/filing down the excess until there is a perfect fit.
MS Paint Skills
The most important part to place your tape/epoxy is at the portion closest to the hop up chamber. If you miss this spot, the hop up chamber will continue to wiggle.
Here's mine. I used JB Weld.
Notice how I only put the JB Weld at the top of the mag catch, as I said before. Pretty? No. Effective? I have no wiggling whatsoever.