Paintball

[dallenmarket]

I was looking at the internal EC mod on the VM Empire site and was impressed with how simple the mod was especially since it can be done without having to go with a longer back bottle line.

I have a few questions though.

1. Does it work as well as an external?
2. Any velocity/blow back pressure changes?
3.What size drill bit and how deep for optimum results?

Thanx

Gunrunner

[Menace]

Short answer.

1. Nothing beats an ext. EXC;

2. Probably not noticable;

3. To a degree, the limits are your ambition and the meat in the marker. I'm not sure if a certain size is recommended in VM Empire. But in any case, if you aren't a machinist, or are otherwise inexperienced, use caution. I've never tried exploring the outer limits on this one, so I can't answer as well as Chaos or Evil Ed or Lovecraft could, or some of the other gang in here. Conservative is best. You can always go bigger and deeper, but you can't put metal back. I would await more experienced advice from some of the more hardcore tinkerers here.

Cheers.

[Anonymous Coward]

Don't expect to gain anything more by making an internal EXC, unless you still intend to run a horizontal bottle under the barrel. A simple TASCO or gutted ACI EXC would do more for you, over the small amount of extra volume you get with a internal EXC. However with a horizontal tank, the internal chamber is your only option; minus a RG-1 (or a CMI International R-2000; they are the same thing) inline regulator.

Everyone has their own secrete sauce that they prefer. For me I want a dump chamber to feed the valve. Modern EXC use some sorta of baffles that restrict the flow of compressed gas. These baffles usually are referred to as heat fins or chambers. Once CO2 rushes in there and the metal chills they don't do much. It's more about the outer wall surface area. I use a simple TASO chamber, it's the closest modern day equivalent to the EXC-68 model. It's a single chamber with a siphon rod running down the center. This allows me to feed the beast and to stave off shoot down a but longer.

Here it is on eBay.
TASO 3 stage paintball expansion chamber autococker - eBay (item 130294428080 end time Mar-24-09 12:50:13 PDT)

[Menace]

AC's advice is sage.

Old tech is still mighty effective, and I concur with his EXC of choice. Good, simple stuff. And even more effective with Cooper T hardware!

Unless your aim is just to have fun machining, there are infinitely better ways to spend time at work on the mighty VM.

But definitely get specific advice on limits before proceeding.

And definitely get some marker pics in here.

Cheers.

[HP_Lovecraft]

It does make a difference, but like said above, if you can get a cheap E/C, it will most likely be better. The real advantage of the internal E/C is you get to keep the VM stock looking, without the negative of 100 shots/7oz

Later model VMs actually came with the mod from the factory. They must have seen some come in for repair, and thought "Hey, thats not a bad idea".

In generally, lots of smaller holes are better then a single large hole since it creates larger surface area for ambiet heat transfer. But in reality, its a bit tough to get in there with a drill press, and other tools, so just do whatever you can do, and pay close attention to the bounderies of the gun.

[Darth Sparky]

I found that this mod made a huge difference over no e/c.

When doing this mod I found something very interesting though. The gas transfer port between the ASA and the valve was only 1/8" in diameter. Nowhere near the diameter of the largest hole on the valve. I drilled it out to match the large hole on the valve. I forget if I used a 1/4" bit or a 3/16" bit.

I had no e/c to compare to and I also changed two things at once so I cannot say if the internal e/c was as important as increasing the airflow to the valve was the more important of the two. I can say that the difference was day and night in terms of reliability and consistency.

David

[Anonymous Coward]

My two cents is it's the transport port from the ASA to the valve that did it for you. {And awesome catch by the way. A true tinkerer.} Increasing the flow rate will do a lot more for you than increasing the reservoir size.

[Darth Sparky]

Originally Posted by Anonymous Coward

My two cents is it's the transport port from the ASA to the valve that did it for you. {And awesome catch by the way. A true tinkerer.} Increasing the flow rate will do a lot more for you than increasing the reservoir size.

I've always suspected as much as well. However I suggest that if you are removing the ASA that you should do both. I think that I read, way back when, that later VM's had a larger transport port.

Expansion chambers, internal or external, only help when using CO2 right? If so then it is the larger transfer port that helped as I ran air for most of the time after the mod.