mcarterbrown.com  

CCI Home of the Phantom Pump Gun

Reply
 
Thread Tools Search this Thread
Old 03-16-2014, 08:59 PM   #11 (permalink)
.
 
The Inflicted's Avatar
 
Join Date: Sep 2008
Location: Chattanooga, TN

Quote:
Originally Posted by Wraith View Post
I don't remember the pressures offhand, but a reg will do wonders for keeping your velocity consistent because it stops pressure creep as the day gets warmer and the CO2 starts to expand more easily from ramping up your velocity.
Thing is, if the temperature is rising your paint is going to swell too, so with or without a regulator you really need to re-chrono anyway.
The Inflicted is offline   Reply With Quote
Old 03-16-2014, 09:09 PM   #12 (permalink)
Seasoned Member
 
1996XJ's Avatar
 
Join Date: Nov 2007
Location: Michigan

With stock springs the Phantom valve system seems to self compensate for changes in input pressure.

When the pressure is high, the pressure behind the valve causes it to shut faster, but as pressure drops, the valve closes slower, therefore allowing more air to escape and somewhat compensate for the lack of pressure. Basically the dwell varies with the input pressure.

I've played with a reg on my phantom, and the velocity stays fairly consistent from 500psi all they way up to ~900.
__________________
Quote:
I think wearing camo is dishonorable. No honorable player would pretend to be a tree or bush.
Quote:
Originally Posted by Ryantuomi View Post
I always close both my eyes and use the force.
1996XJ is offline   Reply With Quote
Old 03-17-2014, 02:13 AM   #13 (permalink)
I'm Stock Classy!
 
Slim's Avatar
 
Join Date: Dec 2010
Location: Connecticut

Quote:
Originally Posted by 1996XJ View Post
With stock springs the Phantom valve system seems to self compensate for changes in input pressure.

When the pressure is high, the pressure behind the valve causes it to shut faster, but as pressure drops, the valve closes slower, therefore allowing more air to escape and somewhat compensate for the lack of pressure. Basically the dwell varies with the input pressure.
If this were true, then players would be able to set their velocity to shoot 280psi in high 60 weather, and wouldn't have to adjust it later on in the day when the temps rise into the 80/90s because the valve would compensate for the change in input pressure as you describe.

However, I've never seen a Phantom (or any other CO2-based gun) whose valve has the ability to automatically compensates for changes in temperature/pressure.

Large temperature shifts are pretty common for late Spring/late Summer/Early Fall around here. Through first-hand experience, I and many of the guys I play SC with know that we need to re-chrono and readjust our guns accordingly to compensate for the 20 to 30 temperature shift in order to stay within the legal velocity limits of the field.

Quote:
Originally Posted by Canebrake View Post
So for you guys who play with large temperature fluctuations throughout the day, does a reg keep your velocity consistent? Without a reg do you notice psi fluctuations on your gauge? Could anyone tell me the average psi a 12 gram delivers, what should a gauge on the valve body be reading?
Again, the pressure of CO2 is determined by temperature. At 70 F, CO2 obtains a gas pressure of 852.8 psi when confined in a vessel (doesn't matter if it's a 12-gram cylinder or a 12 oz tank). There is no "standard" gauge reading. Your gauge reading will be based on how the temp is effecting the CO2 pressure.

Read this LINK for more info on CO2 pressure.

Yes, a stabilizer should help to decrease large fluctuations, but that's not always the case. I use my stab to fine tune my velocity in the AM before the game. By late afternoon, I may or may not have to readjust the stab pressure depending on how hot it got.

Here is an example of temp and CO2 pressure...
In January I tested an un-regulated Phantom in 10 F weather (61% humidity, bore-matched barrel) using 12-grams that had been left in the 10 temps for over 5 minutes. The first 12-gram produced an amazing 9 usable shots over 250fps with a gauge reading of just over 400psi after the first 6 shots. The second 12-gram (which had been sitting in the cold a few minutes longer) produced 1 usable shot over 250fps. As we all know, this same test conducted in 80 weather will yield drastically different results because the pressure will be considerably higher.

Here's my thing with gauges... the majority of them are crap. Just cheaply made crap that have dubious accuracy. PPS sells Ashcroft gauges that boast a 2% accuracy rating. They don't list the accuracy rating of all their other gauges (which I believe they used to do), and I doubt they're anywhere near 2%. These cheap gauges are just there to "look cool" and give you a ballpark idea of what's going on.

Listen, if you're getting over 20 shots per 12-gram with an average of 280fps to 260fps then you're doing pretty good. You don't need a gauge for that.
__________________
Tactical Assault Command
one of the oldest teams in paintball with original members still playing!


Authorized CCI Dealer Specializing in Phantom Repairs and Custom Work
Serving the Greater Fairfield and New Haven County Area of CT Exclusively


Slim's Spring Stock Classic - USA vs. Canada!

Buy my BadAss Stock-Class T-Shirts


My CCI, RTR, Carter, Flasc and TechT Stock-Class Parts Purge

Quote:
Originally Posted by Slim
There's playing paintball with a stock-class gun, and then there's playing stock-class paintball. Big difference.
My MCB Feedback

Last edited by Slim; 03-17-2014 at 02:16 AM.
Slim is offline   Reply With Quote
Old 03-17-2014, 07:20 PM   #14 (permalink)
MCB Member
 
1shot's Avatar
 
Join Date: Apr 2013
Location: MN

Opinions on phantom w/ Gauge

^^^^^ Slim is dead on. I would add that your gauge may or may not be accurate but it is probably precise. Accuracy is how close your gauge is to the actual value. Precision is how close your gauge reads psi over and over again. So if your psi is 850 and your gauge reads 800-900psig average ing at 850psig it could be considered accurate but not precise. If the gauge reads 1000psig every time it is very precise but not accurate. I chrono my gun then check my psig and make a mental note. If I notice an increase between my chrono rechecks through the day, I stop and rechrono.

Last edited by 1shot; 03-17-2014 at 07:24 PM.
1shot is offline   Reply With Quote
Old 03-17-2014, 08:58 PM   #15 (permalink)
...
 
Canebrake's Avatar
 
Join Date: Mar 2014

thanks guys. ^^ exactly what my next question was going to be. So you DO notice a psi increase on your gauge as the day goes on and gets hotter? An increase in psi would mean an increase in velocity (simple physics?)? I live on the Southeast coast and we have major temp increases from morning to afternoon.
Canebrake is offline   Reply With Quote
Old 03-17-2014, 09:19 PM   #16 (permalink)
MCB Member
 
1shot's Avatar
 
Join Date: Apr 2013
Location: MN

Yes, as the temperature increases so dose pressure. Velocity will increase with pressure although there is a limit to this. For the pressures we are talking about on a Phantom valve, increased temp = increased psi = increased velocity.
1shot is offline   Reply With Quote
Old 03-17-2014, 11:56 PM   #17 (permalink)
Radical!
 
nerdcore's Avatar
 
Join Date: Nov 2009
Location: NishNash

Mine came with a gauge. I looked at it once when i first popped in a 12g, then again when i first aired up with compressed air. Sooo, only out of curiosity and not necessity. As is usually the case, the chrono is the only reading i care about.
nerdcore is offline   Reply With Quote
Reply

  mcarterbrown.com » Paintball » The Armory » CCI

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump


All times are GMT -4. The time now is 06:28 AM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO
© MCB Network LLC