SpudFiles

This is "H.E.A.L.", or usually, just HEAL without the periods.
HEAL is simply an acronym of the words "High Efficiency Air Launcher".

More specifically, it's HEAL v1.3, because it underwent a couple of minor rebuilds, then a pretty major one that changed a couple of things.
It cost me about £300, roughly $600 USD, through the various revisions, including the custom pump but to build it again from scratch would cost a bit less. A pretty large amount of money, but you get what you pay for - and, correspondingly, this is the single most powerful cannon I have ever built, out classing my old combustions in twice the bore size.

The design took into account most of the comments I had about my last cannon, Behemoth, making it both powerful, and reasonably good looking.

The length is about 29 cm longer than which ever barrel I am using, so for the current 125cm barrel, 154 cm. It weighs in at ~4.2 kg without attachments ,and increasingly more with attachments such as the suppressor, bipod and laser module. (Not shown in the pictures)

I can take it up to 22 bar (320 psi), but I usually use it at 10 or 15 bar. The valve is an optimised 22.1mm seat diameter piston valve with smooth flow edges to up the efficiency, piloted by a 1/2" QEV.

It has various barrels, two in 20.3mm bore, of 100cm and 125 cm, which have a basic sliding breech and a 26.3mm bore barrel in production, of currently undecided length - which will be muzzle loaded.
The chamber is 26.3mm ID by 120 cm in length.

I also have a few known muzzle energies and velocities for the 125 cm barrel. Typically, it will get about 400J at 300 psi, but with a heavier projectile, it will theoretically manage 580J.
I also managed to record an approximate muzzle velocity with a paintball, which clocked in at somewhere over 300 m/s (~1000 fps)

Some photos of it a little while ago. It has now got a bipod and muzzle twist lock, but I haven't got photos of that. (Also, I can't take them, as I don't have HEAL at the uni with me)

Full length picture
Rear
Valves at rear
Breech, handgrip and guard
Polymorph grip
Homemade high pressure pump

I'm afraid there are no videos, but I found this damage pic on my phone:
Frozen paintball through water filled box at 10 bar (there was a bin liner inside)
No doubt, I will get pointed at "The Box o' Truth" and asked how thick the box in question is. The box was 8 inches deep when the weight of the water forced the sides out slightly - and the paintball still exited the box doing a fair pace, making a mess of my backstop.

I know that I could punch tougher ammo through well over 12" of water, because my previous, less powerful cannon, Behemoth, could put a 3/4" steel ball bearing through 24 gauge steel, then 12" of water, then another layer of 24 gauge, then leave with enough velocity to make a hole through the 3/4" thick fence behind, and still leave into the fields beyond to never be seen again.
After that, I started using a backstop. (Normally a hefty chunk of tree stump that we have in the back garden from a tree the family had extracted several years back).

All the other photos are on the computer at home I'm afraid, and I'm not there until at the earliest the weekend after next, so there's a bit of a wait for more pics.

EDIT:
The video for your entertainment:

EDIT: Youtube vid down, you'll need Photobucket: Link to Photobucket mirror

No doubt, I will get pointed at "The Box o' Truth" and asked how thick the box in question is

predictable, aren't I

Very nicely done, particularly the pump. I can't imagine taking a chamber that big past 300 psi with my shock pump.

i like the grip alot and the high pressure pump is awesome! the 100fps is not bad either

How did you end up spending $600 on that? I mean, how, just how did you manage that?

Very nice copper gun. I like- well, all of it.

-goose_man

Btw though, very very nice gun!

ammosmoke wrote:How did you end up spending $600 on that?

Welcome to the UK, the place where everything costs shedloads more.

I guess so! Man, copper costs me about 10-20 bucks for a 10ft length!

the copper isnt that bad over hear...but the fittings ect are pricey..add in a slide valve alot of jubilee clips, a QEV and it soon adds up....welcome to the UK lol

SWEET! I love this cannon! It mut be soo fun to shoot. Good soldering job too.

all it needs now is a high pressure/flow compressor and a mag feed

jackssmirkingrevenge wrote:predictable, aren't I
Very nicely done, particularly the pump. I can't imagine taking a chamber that big past 300 psi with my shock pump.

You yourself mentioned how long ago my account was created. I've been lurking for a while.
I've done quite a few hydro penetration tests over time, although I don't tell people quite what the numbers mean.

I made the pump specifically because I neither have access to a 300 psi compressor, or the will to pump it up with a shock pump. Still takes a moment, as the pump has to have a low volume even in the track pump configuration.

@ALIHISGREAT:
1000 fps not too bad? Few pneumatics can manage much more than that. (Ignoring the Airforce Condor.)

@ammosmoke:
There's a few things that cost a bit you don't see. The laser module and circuits were about £20-30, the pump must have been at least a quarter of that, there's some stuff I bought for the first version I later replaced (for which I didn't subtract costs), a couple of things I bought I didn't later use, and of course, we pay about the same in GBP as you would USD.

The general rule of thumb is that regardless of the nominal exchange rate, it really is a 1:1 ratio (even if ordering across the Atlantic - the shipping and taxes will add up to about 1:1 again)

For 3m of 22mm OD copper (Approx 10ft long, 0.8" internal diameter), it'll cost maybe the equivalent of $25 at best. Fittings are a little expensive too.
However, most of the cost is eaten up in specialist pneumatic components, not the pipe and fittings.

But believe me, it's worth every penny.

@spanerman:
Ok, if you can find a reasonably priced 300 psi compressor, I'll try that.

@iPaintball:
It's pretty fun for a moderate number of shots a day. After that, at higher pressures, the pumping and recoil can get a little wearing on the arms.

@goose_man:
Thanks for the compliment.
It does have a couple of downsides though. It's pretty heavy, but that does help absorb recoil nicely. It's also loud without the suppressor (which itself weighs a bit).

Did a bloody amazing job there Rag. When/if I get some money, I will make something like that, but I have a slightly better idea for the valve, but I'm keeping it a secret

One question though..Is there a good seal at the breech load? Because it seems as though it's just copper sealing against copper, or is there an O-ring in there?

i belive he used an o-ring in there..i have to in mine to get it to seal

It's 22mm pipe going straight into a 22mm fitting, with the 0.05mm gap packed with silicon grease, but no O-ring. It's practically completely leak-free anyway.

I'm intrigued by your claim, but still, you'll have your work cut out beating that valve.
It's built with a 22mm fitting internally to increase the seat diameter, remove hard edges in the flow (constricting flow less, and producing a more powerful laminar flow)and increase opening force.
The piston has a check valve built in, the pilot volume isn't too large (and even if it was, it's piloted by no less than a 1/2" QEV), the flow paths are optimised... it's quite a serious bit of engineering.

That valve and 320 psi together is pretty impressive to see, but more horrific to hear, and should not be approached without either ear defenders or ear plugs. And the suppressor too if possible.