I have seen several threads here on ASR recently asking questions over these mods. Well, I wanted to share with the sniper community what I have done and why I have chose to do them. I will try to cover each modification in detail. The first two mods may be applied to rifles other than the VSR/BAR 10, however, the brass shims are specific to the BAR/VSR 10 hop-up unit.Clay Stock Mod for VSR/BAR 10
This modification use non-hardening and reusable modeling clay. The primary purpose of this modification is to reduce the noise output of the rifle firing by reducing the amount of echos created within the hollow stock of a VSR/BAR 10. Furthermore, this mod will also add weight to the rifle which is great for balancing a heavy outer barrel such as the PDI Outer Bull Barrel. The added weight will also make your rifle feel more like a real steel rifle.
The first thing I did was filled the entire butt stock with modeling clay as shown below
Next I filled the entire front portion of the stock with the modeling clay as best as I could.
The modeling clay is great because it will stick to the walls of the rifle allowing you add clay around the trigger mechanism. This will further reduce echos created within the stock and it is very important to add clay in this area since these hollow spaces are closest to the source of the noise (piston hitting cylinder head).
In addition, The Crimson Falcon and Nickswimsfast provided a great idea that I did not think of! They suggested that clay be added around the trigger mechanism to help reduce the amount of noise that exits from the cylinder. The photos below were provided by Nickswimsfast.
The modeling clay that I used is called "EZ Shape Modeling Clay: Non-Hardening and Reusable." I purchased this clay for $4.99 a box at Joann's Arts and Crafts Store. The Stock Clay mod will require 2 boxes to complete; some clay will be left over. I am sure this clay can be purchased at any arts and crafts store.
Lastly, what makes this mod great is that it is not permanent. If you dont like it, simply scoop the clay out and clean the stock with a wet rag. With its very low cost, this mod is definitely worth a try if you are thinking of adding weight to your rifle or trying to reduce the noise output.Clay Stock Mod for L96The following words and pictures were provided by StEaLtHlEaD and I take no credit.
Okay so this is what I did. SVT feel free to add these pictures and words, even change them I don't mind at all, it would be an honor in fact.
For anyone thinking it would be tough to do the clay mod with an L96 well, you thought wrong. It was actually pretty easy. Getting it apart took longer then the process of adding the clay. I have a UTG L96 which is the same as WELL, warrior, etc. so this should be similar to all L96's I assume. I started out taking everything apart; the upper receiver/barrel unit completely off, all the body screws taken out, etc. I cracked open the plastic body in disgust.. I really don't like split bodies like that, it makes it feel all cheap which is what I was thinking ever since I bought this gun. I used the clay SVT said except it was multi colored. Same material, same weight, just different colors. Here is a picture of it:
So yea that's really about it. This is very obvious; the clay goes into the stock. Main things to mention here is making sure the cheek rest block, trigger unit, and weights can fit tightly. I put clay under the weights which I highly advise; remember any empty space means more sound. Here is the first half. You just smooth it down pretty much with your hands. Just like in arts and crafts..
Yep. Same thing with the other side. Here are the two pieces next to each other.
Since L96's are built differently, you can't quite add the clay the same way SVT did originally with his VSR10. I added a bit of clay into the metal box thing in the stock, and I will most likely add a bit more to the middle/front end of the gun. This mod adds A LOT of weight!! It feels a lot better, in fact is a bit to heavy on the backside now. (Which I love!) Another thing to note is the stock pretty much stops creaking, and making cheap plastic sounds. It feels 10000x times more realistic and I am very impressed with the results of this! So yep, that's about it. Enjoy! Foam Stock Mod for L96The following words and pictures were provided by xbeeongx and I take no credit.
Not to steal SVTCobra or StealthLead's thunder, but since there are now L96's involved in this thread, I'll just add this little bit. The L96's already heavy body combined with the difficulty of separating the body drove me to seek this alternative to the clay: foam.
This is just plain, somewhat squishy foam that can be seen lining the boxes of many products. It is squishy and it easily rebounds to its original shape if squeezed. In the above picture I cut out long strips and just smushed them into the handle / stock area, all without having to split the body in twain. There is enough foam in the handle to take up twice the stock's volume, but the foam squishes so that's why so much was added.
Below is a picture of the foam placed in the area right next to the trigger, with a slot cut out for the spring guide stopper. L96 users are familiar with that metal frame in which the trigger and receiver fit. In the metal frame is a hollow cavity, directly in front of the trigger area. The foam was also cut to shape and stuffed in there to reduce echo.
I also stuffed the foam into the hollow ribs of the body where the outer barrel rests.
Not pictured is the area right in front of the mag release. If you use the stock hop up chamber, you cannot do this foam mod as well, since you need to have unobstructed access to the area in front of the mag release in order to adjust hop up. For those using the PDI hop up, the area in front of the mag release will no longer need to be used, so you can just foam it up.
The most reduction in sound will come from padding up that empty cavity in the metal frame in front of the trigger. The foam will not be as good as the clay, but with its rebounding advantage I also added some of it directly INTO the zero trigger for my L96.
I have played dozens of games since doing this foam mod to the trigger alone, and and has never jammed.1 Piece Barrel Spacer
The importance of a 1 piece barrel spacer is to boost the accuracy of your rifle by damping the vibrations sent through the inner barrel from the piston hitting the cylinder head.This mod is very simple to do, however it requires that your rifle has a cylindrical outer barrel such as those found on the L96's or the PDI Outer Bull Barrels for the VSR/BAR 10's. All I did was wrap the inner barrel with sheets of computer printing paper until the paper spacer fit perfectly within the outer barrel. I used clear tape on the entire edge of each sheet to hold the paper down. The sheets were wrapped tightly, however it is not required that they be perfectly wrapped. In other words, wrap the sheets as tightly as you can but don't feel that you need to remake your spacer if it is slightly "squishy" in the end (I will explain below). The spacer should fit within the outer barrel snugly; it should not wobble or slide loosely, nor should the spacer fit so tightly that you have difficulty sliding the barrel in and out of the outer barrel. My spacer looks like this
You may notice the small black spacer at the front of the barrel. I reused the stock BAR 10 front plastic spacer by shaving it down to size. I have used this spacer for almost 1 year now and so far it has worked great for me. I noticed a large improvement when I switched from the stock BAR-10 spacers to this 1 piece spacer. Computer printing paper is great for damping vibrations since there will be small amounts of air trapped within the sheets of paper. These pockets of air will cushion the inner barrel when it starts to vibrate. Brass Shims for VSR/BAR 10 Hop-Up Unit
These shims are used to solve curving problems with the BAR/VSR 10s. I am not going to cover the problem here since Noobie has adequately explained the problem and covered the solution in his BAR 10 Project thread
. What I will explain is how I made my shims and the reasons why they are shaped the way they are.
The shims are made from Brass Shim Stock which can be purchased at a hardware store such as ACE. There are various thicknesses that you can purchase; I chose the smallest thickness because shims can be layered upon one another if they are too thin. The cost of the brass shim stock is roughly $2.
For the left side
of the hop-up unit I cut a rectangular piece with a pair of scissors like so.
It is important to have a full length shim because it will ensure that the hop-up arm does not rotate horizontally. It is my opinion that AEG shims will not suffice with the BAR/VSR 10 hop-up unit because they will not give the benefit of a full length shim (which is the prevention of horizontal hop-arm movement). The center hole was cut using a drill bit slightly larger than the hop-up arm stud. I forget what was the size of this drill bit, however if I can find it again, I will update this thread with the size. Make sure to add steady pressure to the shim while drilling the hole. Although, dont add too much pressure or else you will tear and ruin your shim. I used an electrical power drill and I found that cutting was cleanest using very low rpms. I also cut my shims on top of a thick magazine so that I would not ruin my desk; I am sure something similar such as a block of wood will work just as well.
The shims for the right side
of the hop-up unit are made in two different ways as shown.
This shim can be made into 1 piece or two pieces. The top of the picture shows a 1 piece shim and the bottom shows a two piece shim. Either method will work just as well, however, I found it was much easier making a 2 piece shim than a 1 piece shim. The 1 piece shim was made by cutting a strip of brass down the middle of a left side
shim. The 2 piece shim was made by cutting an "L" and a straight piece, making sure to trim them so that all hop-up parts have a perfect clearance.
You may find that working with the brass shim stock maybe a bit frustrating at first since the shim stock is easily bent. I found that a bent shim maybe salvaged by placing it on a hard surface (such as concrete or metal) and flattening it back out using a hammer. You can bang the shim multiple times and then finish off by "grinding" the shim with the head of the hammer using horizontal movements. The shims were attached to the walls of the hop-up unit using Elmer's Glue Stick. This glue is great because it will hold onto the shims tightly enough for airsoft purposes, but not so tight that you have to ruin your shim to get it off if you need to change/repair/re-glue your shim.
Lastly I want to give some credit to Nshadow for these shims. I first learned about shimming from him, then after many attempts, I perfected and made the custom shims I have shown above.Brass Shim For VSR/BAR 10 Hop-Up Arm
One method you can improve the tolerances of you hop-up unit is by reducing the amount of slack between the protrusion of the slider arm and the horizontal cut-out in the hop-up arm. The goal of this mod is to make the whole system a tad bit more rigid. Its main focus is on keeping the protrusion and hop-up arm as static as possible during firing. Your shots will be more consistent since the applied hop-up on the bb will be more consistent. Ideally you want your hop-up unit to to remain completely motionless during each and every shot. This mod should help your hop-up unit reach that idealization; especially when coupled with other hop-up unit mods.
This mod is done by placing a brass shim inside of the horizontal cutout; the shim gives a much more snug fit to the protrusion from the slider arm. To perform this mod start off by using a small flat file and sand away any cast lines inside of the horizontal cutout. Make sure both the top and bottom surfaces of the cutout are as flat as possible.
Next take some of your shim stock and cut out a shim that fits inside of the horizontal cutout. My shim happens to be 5.4mm x 19mm. Make sure to test fit the shim inside of the cutout and remove excess material if necessary. If your shim happens to bend/warp/twist during cutting, you can re-flatten the piece by lightly banging on it with a flat head hammer on a flat hard surface.
Once your are satisfied with the piece, glue it inside of your horizontal cutout. I always start off with Elmer's glue because its a weak strength glue with a slow cure time. This glue allows for multiple attempts because its residue is easily removed without damaging the hop-up arm or shim. If the Elmer's glue proves to be too weak, then you can upgrade to super glue. However, I suspect that the Elmer's glue will be strong enough for this mod.
Give the glue at least 15 minutes to dry and then test fit the slider arm protrusion inside the horizontal cutout. The protrusion should have a snug fit; not overly tight nor loose enough where the arm moves freely. If you take a look at the picture below, the hop-up arm will remain static on the protrusion no matter which angle I hold the piece at.
I also made a ring out of the same shim stock to shim the hop-up arm protrusion with the hop-up shell. This shim is held with super-glue because the extra strength is needed.
Well feel free to comment, criticize, and share your experiences. Thanks for reading!