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bsolomon
04-11-2002, 04:52 PM
There have been many threads discussing factors that go into the decision of which size/pressure HPA tank someone should buy. I thought I would try to simplify things by making an HPA tank sizing guide. Let me know what you think - (owners of the various tanks please let me know if the shot estimates are approximately correct).

In order to get the values on the chart, I used the following logic:
The first column is the size/pressure combination for the most popular tanks. Begin by multiplying the tank size in cubic inches by the maximum pressure in pounds per square inch. The units work out to in-lbs, which is a measure of energy/work available by the air in the tank. The next column is used to determine the portion within the tank that is not usable due to the fact that there is a minimum pressure required within the tank above the output pressure setting of the tank regulator. For Mags, assume an average output of around 750-800 psi, and therefore a minimum usable tank pressure of about 1000 psi. Subtract the unusable energy/work from the total available to arrive at the effective energy/work value for each combination. The
data is then all indexed to a standard combination of 68/3000 with a value of 1.0. Compare the index values
for each combination to determine the relative number of shots you can expect for each tank. For those who
like actual numbers of shots, the final column assumes about 650 for the 68/3000 tank, and multiplies by the
index values for the effective number of shots.


HPA Tank Sizing Chart:

http://www.users.qwest.net/~solomonbarry/images/tanksize.gif

Mav D MagMan
04-11-2002, 05:13 PM
I must say... Thank you! Although problem is gas hogs and the like will have a problem living up to those expectations... ;)

pip_999
04-11-2002, 05:47 PM
wouldnt it vary on each gun?

BTAutoMag
04-11-2002, 06:12 PM
good job but what do you mean by total, unused, and effective?

Croix71
04-11-2002, 07:41 PM
Thanks for the chart. I'm guessing the # of shots should be used as a baseline number since it would vary per gun? :D

RobAGD
04-11-2002, 08:59 PM
I would say that those number are on the low end as to what to expect.

On the 68 3000 and 68 4500 those are about right for using a SP AA 12" barrel or a Dye Boomie or Ultra Lite.

With a Stock RT Barrel my number goto about 1000 on a 68 3k and 1500 on the 4500.

That is part of the precived problem with mags is that the barrel and paint make such a massive differnace in how much pressure you need to punt a ball out the end of a tube.

I run 650-1000 on a 68 3000 and the only thing really changing there is the barrel.

Barry - Nice to see you posting :) Marks been drooling over the C&C I have at the shop for display :)

Thinks warming up in the mountans yet ?

-Robert

Rooster
04-11-2002, 09:33 PM
With a dye alum that number is right on for my 68/3000 preset.

bsolomon
04-12-2002, 08:38 AM
Obviously I know the "your mileage may vary" based on your actual marker, barrel, etc... My original intention was to only carry out the chart as far as the index, which of course lets you compare each tank combination in a relative sense. However, I know AO's are far more practical than that, so I dropped in a rough guess on the number of shots.

There are really two uses for the chart: if you have never had HPA on your marker, it gives you a good place to get an initial estimate of what you can expect, and if you do have HPA and are planning an upgrade, the chart makes it easier to decide on what you are likely to need based on your style of play. The second item was really the reason I even did this. I currently have a 114/3000 on my Mag, and I am planning to get an E-Mag Extreem as soon as they are available. I started the exercise because I wanted to see if I needed a 68/4500 or 88/4500 to get about the same number of shots as I currently get.

For clarification, Total represents the theoretical amount of work you can expect out of each tank, Unused represents the amount of work you will not be able to get out of it based on the outlet pressure setting of the tank's regulator, and Effective is what's left to actually make the marker shoot.

For RobAGD - the snow's finally melted. Playing an office game at the end of the month, and the next DBD event I will make will be MXS ShadowBreed at ChallengePark, Chicago in June. Consider me drooling also on the C&C, but I know you'll come up with something suitably exciting for me!

Snooky
04-16-2002, 09:50 PM
i can get around 600 shots approx with my 47/3000. but i think the chart is helpful and gives a good idea on what to expect.

Sinnet
06-19-2002, 09:28 AM
w/what barrel snooky?

Polishpickles451
06-19-2002, 09:54 AM
i can get above 600 with my minimag stock barrel using a 47ci

J
06-19-2002, 01:45 PM
My friend gets only about 400 shots off his 47/3000, of course he does have a 16in all american...