water gun conversion

Hi everyone, Just thought i'd share a work in progress with you all.
I bought this Super Soaker triple shot at a garage sale for $2.





I took it apart and found it had a nice strong firing valve, which would dump all of the air in the tank in one hit.
at first I tried to use the turret, but eventually decided that the seal was useless.
I did away with the turret and cut the plastic off the firing valve just before the body, and epoxied a 1/2" brass male/female fitting to it. For a barrel I'm using 15mm poly riser, about 12 inches.




The frustrating thing was having to pump it 60-80 times to get a decent shot off.
I solved this problem by using soft drink bottles, pressurised to 100psi, with a tubeless wheel valve in the cap.
I used the female end of a flexible truck wheel valve extension as the fixing point.




Now I get 5 shots of over 35m (114 feet) without having to pump, and i can keep 2 or 3 more bottles on me at a time.
This was never meant to be my primary, as my recon does that quite well. It does however, make an excellent specialty blaster.

Let me know what you think, I want to add a breech, support for the air tank off the barrel, and a stock.

water gun conversions have been done but I love the bottle idea my water gun conversion get higher ranges and more power but has the 20 pump problem

I think that maybe the barrel I'm using is too short. also the ranges could be increased with better darts/more pressure. at the moment i'm only using my first ever batch of stefans. dart to barrel fit is great, but the weights i'm trying to sort out.

How long is the current barrel?

Looking good to btw, score for 2 bucks.

cheers, the current barrel is 350mm. I was thinking, the reservoir is 570mL, at 100psi. so ideally I would have a barrel close to equal in volume right?

If you put an RSCB on that thing you will end up with a semi auto gun.

I don't know a lot about modding air guns, but I do have a Big Blast with a 6" Barrel which gets around 130ft, maybe your barrel could be slightly to large I wouldn't rule it out, but try both. 350mm Sounds a bit to long.

the thing with a spring gun (if I'm correct) is that the volume of air in front of the plunger head is constant at full draw. the force comes from the spring. that spring can only expel the air that is in front of the plunger head, no more. the whole idea of a proper barrel length is to get the maximum acceleration of the dart before it leaves the muzzle. the volume of air in a pressurised tank changes with pressure, as more air is forced in. or so i understand. so perhaps a longer barrel will yeild better results. will try this tomorrow.

How do you compress the bottles?

I fit tyres to trucks all day at work, so i have an endless supply of airtight fittings, high pressure air, and proper inflation cages in case one pops. I take a bunch of them to work and fill them there, then i know theres no moisture in the air either.