The Completed Hydro Cannon 2500

Now that the first version of the Hydro Cannon 2500 is complete, I can now make some first conclusions compared to stock.  The modifications despite running into a few issues on the way have all worked out well and have not broken the blaster or made it useless as modifications as extensive as this can sometimes do.  You are taking a risk at the end of the day.

Before I go any further, I am going to go through what has been done to the Hydro Cannon 2500 thus far.

-Stock pressure chamber replaced with CPS 2500 chamber and casing
-Trigger trimmed down and reinforced to fit with chamber
-Internals trimmed down and also shaped to fit
-Pieces of internal plastic cut off again to make way for the pressure chamber fitting
-Pressure gauge
-Vertical pump handle part cut off
-Backpack addition
-Part of reservoir still there to fill the dead space at the back and increase capacity
-Mesh screen on nozzle removed for increased range

Stock Hydro Cannon (Top), Hydro Cannon 2500 (Bottom)

First, I will now do a table comparing the statistics in which to draw my conclusions.

HC 2500
1.125L - 39.6oz
4.21L - 148.2oz*
220mL - 7.7oz
600mL - 21.12oz

Shot Time

8m - 26.4'
12m - 39.6'
220mL - 7.7oz
HC 2500
8m - 26.4'
14m - 46.2'
600mL - 21.12oz

Pump Volume
Shots Per Tank
16mL - 0.56oz
HC 2500
16mL - 0.56oz

*Combined reservoir and backpack volume (510mL reservoir, 3700mL backpack)

As you can see from the comparisons between the stock Hydro Cannon and the now modified one, there are improvements.  Most noticeable being how much water you can hold being four times as much.  It does not really feel like you have much weight on either which is good.  The firing chamber too is also three times as big as before, and even with the large increase, you can still get two more shots per full tank over stock meaning you can last a decent amount of times.

The range has now also improved.  This is partially due to the bigger more powerful firing chamber, and also due to the fact the mesh screen has been taken meaning there is pretty much nothing to slow the flow down, making it get maximum range.  On a good blast, the beam and range is like a bigger CPS 2000 beam that gets close to its range, however it shoots for less time.  It really is a rather deadly shot now, which if it hits a target, they’ll be soaked instantly.

The power aspect predictably improved as well, being that it is after all a firing chamber from the CPS 2500 it would be.

It is not all good though, and the bad parts really prove that Hasbro really do not design blasters like 2002 days and before. 

The amount of pumps it now takes is double what it would be stock; this is due to the very poor pump volume.  It looks like the stronger and bigger chamber actually does draw more water in per pump than stock, as it is three times as big, but only takes twice the amount of pumps compared to stock.  If it were the same volume per stroke, then it would take around 60 pumps, alas upon testing it only took around 35-40 to get it pretty much there.  Even so, it is still a lot of pumps for still a pretty short blast, which leads right on to the next problem.

Even with the much bigger firing chamber, the shot time is only increased by around 0.2 seconds.  It ends up being around the same as the Flash Floods ‘Flood’ nozzle.  Part of it is due to the mesh screen being taken off making the water rush out faster.  However the main part is again through not very thoughtful design.  This is due to the size of the nozzle in general.  It’s bigger than the one on the CPS 2000 for crying out loud.  At first I thought that with the 600mL firing chamber which is again three times as much as stock, the shot time would be around a second, however that was not the case.  Even with the screen on, the shot time was still less than a second.  The nozzle size is bigger than I thought, in which as it is you’d need a 30-40oz firing chamber to even get to around a second in shot time.  That 30-40x output per second!  And at that level of capacity with the amount of pumps it would take for this gun it is just overkill.

There is also one other slight explanation for the shorter shot time compared to the CPS 2000, and that is the way the internals from the firing chamber to the nozzle are designed.  Basically it is aerodynamics but on a water gun.  Sounds silly, but yeah I cannot think of another way to compare it.  First of all, here is a not great drawing to show the CPS 2000’s design.


As you can see, upon being fired, the older CPS blasters used pull valves like this, and on the CPS 2000 this is basically what it looked like.  The water did not travel in a straight line fully and had to curve round a bit, reducing the speed it travels out slightly, and with the slightly smaller nozzle, allowed it to shoot for a second while still having immense power.

Now if we take a look at the Hydro Cannon 2500’s internal layout when it comes to firing, things are quite a bit different.


As you can upon being fired the water flow pretty much has nothing to get in its way to make a detour around, it just goes straight out.  Combined with a ball valve and not a pull valve, aerodynamically, the blast erupts out a lot quicker because of this.  Since the nozzle is also bigger, the overall shot time is a lot less.

Because of this, the nozzle on the Hydro Cannon really does need to be smaller, while still being able to retain a good big blast.

There are a few other little issues I encountered with the now modified Hydro Cannon.  I should have when blow torching the reservoir (or what was left of it), done the straight part at the bottom, at the time I did not as that part being simple and straight sealed shut then.  However now there is a leak, which I’m confident is coming from there, so in the next version that is going to be sealed up. 

The backpack tubing when connected on to the Hozelock connector kinks and bends when in use, which over time might cause a problem, so I will be putting a spring in there to prevent it.

Finally, one thing about the Hydro Cannon in general is its trigger.  It is rather dynamic as the blast will depend on how hard and fast you pull the trigger back.  To get it at its best I found that I needed to pull it back as fast as I could.  To be honest I’m not sure if I like the design, then again I’m much more used to the older Larami blasters where it was much more of a stiffer setup, as it was just finger, pull and fire fully!  For the next version I am going to do an adjustment on the trigger.


Issues aside, I was happy with how the first attempt came out, granted, it still does not shoot for very long and takes not the best time to pump, however at least now the Hydro Cannon 2500 does fire a blast that can be counted as deadly if it hits something.  What I have also proved, is that the Hydro Cannon does take quite a lot of time and effort to modify and improve, which shows that stock, as much as I hate to say it, the Hydro Cannon is not a very good blaster.  Even with the current mods to date on it, as you have read throughout this conclusion, it still needs more stuff done on it.

I plan to do the next few improvements in due time, for now I need to get a few more videos and take some shot pictures before the next stage of adjustments happen.  I’ll be glad when I have the shot images done, because the Hydro Cannon is the hardest blaster I have ever encountered to take shot pictures with due to its extremely low shot time.  Most of the time you have to have luck on your side to get a good picture that is worth keeping, honestly, you would have more luck trying to become World Champion of a competitive sport.