These Expansion Chambers are unique in the way CO2 is distributed. It enters the bottom chamber and travels through a series of diamond-shaped cones where the liquid and air are mixed evenly, giving a more consistent flow of pressure to the valving of the marker. Unique to its design, the housing works in any position, even if inverted for remote set-up or crawling situations. If excess liquid is pulled through the system due to rapid firing rates, the diamond-shaped cones act as a centrifuge, slinging excess liquid outward to be recycled through the system.
The ACI Sub-Zero 4 Stage Expansion Chamber is newer, so it should be commonly available, both new and used.
Dragun E-1 - Stainless Steel Turbo Valve, Lapco Cup Seal, Custom Cut X-Raider Series Barrel no porting 10" , Check-It Products Dragun Full Force Delrin Bolt, Check-It Products Dragun Sweet Spot Trigger Flat, Check-It Products High Volume Cell, CMI R2000 Inline Reg with male / female ASA linked inbetween marker and ACI Sub-Zero 4stg X-Chamber, Java High Pressure Coiled Remote, 20oz Pure Energy Co2 Tank, Fed by a VL eVLution hopper. Double Regulated from 775psi bottomline reg, 550psi inline reg.
For its size and price it does a decent job of helping to eliminate "snow." I use it inline with my CMI R-2000. Due to the nature of my marker's set up I required a good x-chamber with a compact size, but still able to do a good job at expanding liquid co2 into gas. Since I would be attaching an X-chamber into a CMI R-2000 reg which added an additional 2.5 inches in length I decided to go with the ACI Sub-Zero 4stg. I felt it would do a better job then other small compact x-chambers and it hasn't dissapointed me.
Like all x-chambers the grip will get cold to the touch after a prolonged period of consistantly firing your marker. Also it lacks a 360* swivel insert, you must loosen the bolt on the bottom with an Allen Key to adjust the positioning of your insert.
For around $30 (depending on where you shop) you can purchase an ergonomical, compact, and functional expansion chamber that will expand your Co2 giving you more shots, as well as being pleasing to look at. They come in various colors allowing you to match your marker. No more frankenstien appearances. I rate this x-chamber at an 8.5 but since I can't select 8.5 I'll just select 9 to round it up. If you plan on a compact space saving set up then I recomend the Sub Zero 4stg, if you could care less about bulk then I would point you in the direction of the Sub Zero 6stg.
Spyder, Booyah ELCD Frame, ACI Exp. Chamber, Shocktech Rear Cocking Bolt, 14" Dye Aluminum Barrel, ACI High Volume Cell, Raised Sight Rail, Champ Sight, Gas-through Stock w/ Remote Line, 68cu PMI Pure Energy Tank
Makes the fps much more consistent therefore accuracy is improved.
Fits very nicely in your hand and the it can be twisted so that the hose will face the bottomline.
If you don't know exactly what you're doing when you install it, you may want to get someone who does to do it for you. Also, you have to buy an adapter seperate to fit into the gun. Atleast that's how it was for my Spyder BL.
A must if you plan on playing in cold weather with co2.
Joker STP with a drop forward and a rear velocity adjuster
Improves gas consistency, great forgrip, looks cool
takes an adapter to fit my gun, only comes with asa threads
Very nice adition to my gun. My velocity went from jumps of 10-50 fps to only 5-8fps. Very helpful. Great forgrip help. Takes a mini cocker adapter from ACI to fit my gun. Great price, only 31 after shipping. Easy to install and adjust. Gave it a 9, because there are no threads for my gun, only asa .
It gets the job done, period. I play in cold weather alot and my gun has run perfectly. It's well worth the price of about 30 dollars online. The colors are great, and it makes a great foregrip. Shots are more consistant.
This works as well as any other expansion chamber. I would recommend this to anyone with any gun that plays in cold weather, or anyone at all.
A really great expansion chamber i like turn off my on off valve on my tank and i get like around 20 shots or more just to empty out what is left so it is really good on efficency it usually only takes about 6 shots and it is emptyed out.
The ACI 4 stage expansion chamber is great. It was worth the money. I used to have ice coming out of my barrel, and now thats gone. The rate of fire is good and when i used to shoot without the expansion chamber my gun froze a lot, and now thats gone and im happy with this expansion chamber
There is nothing wrong with this expansion chamber. I say it is worth the cash.
This expansion chamber is worth the money and I think ACI made a good expansion chamber, and I reccomend this expansion chamber to anyone.
Keeps liquid out of my gun.
nothin.....just make sure you put teflon tape on your hose before you put it in the chamber.
I got mine for 30 dollars which was pretty cheap. I use it on my Piranha BL VF and it works great. I used to have 'snow' come out of my barrel when i shot now it works fine, no more ice/liqiud. It keeps the velocity more consistent. I'd say the only bad that is when u take out your CO2 more is wasted but thats normal for any xchamber or regulator. I recommend this to anyone that uses CO2 or doesn't have an anti siphon tube.
I recently installed this on my Piranha STS G2. The expansion chamber works as advertised by keeping liquid CO2 out of the gun. However, just to be safe, if you're shooting CO2, don't point your gun toward the ground. This allows CO2 to flow into the expansion chamber and could cause some serious velocity spikes. Because the chamber provides extra space for CO2 to convert to a gas, it allows for more consistent velocity. Since I've added the chamber, I've noticed that my velocity spikes range about + or - 5 FPS. Before I put it on, they ranged + or - 15 or more FPS.
ACI does not provide instructions for installing the chamber. It's obvious that it screws into the vertical ASA, but there should be something to explain how to loosen the chamber housing. You have to do this in order to properly run a bottom line to it. As explained in an earlier review, an allen screw at the bottom of the chamber has to be loosened. I had to call ACI and get one of their reps to tell me how to do it. Then, after he explained it, I slapped myself because it was so easy.
I got the chamber for about $40. It was the best price on the Internet. As stated above, it works just like advertised. If you shoot CO2, this is a good upgrade, especially if you don't plan on changing to an HPA tank or converting to low pressure.
9 out of 10
Last edited on Saturday, January 29th, 2005 at 7:33 am PST