SpudFiles

This is a cannon that was made a long time ago. It was supposed to have a smaller chamber but I decided that if it is worth doing it's worth over doing.
It was designed mainly by me but I talked with Larda through the entire process.
Larda (a spudding machinist) gave me good prices on materials and work so I gave him the job of constructing the chamber.
The construction would be nearly impossible for me without heavy machining tools.
He did a real good job, thanks Larda.

Lets go through some specs:

Mix: 3-10x propane/air.

Material: all steel with a few brass fittings that can't be found in Norway in any other material.

Projectiles: Lead slugs in different shapes and steel penetrators.

Meter: manometric meter in two parts.

Valve: 2" stainless steel union.

Ignition: Camera capacitor dumped into a ignition coil and into a homemade spark plug in the back of the chamber.

Chamber: 60cm long 5" steel pipe with 7mm thick walls and a 2" end plate in the front and a 3/4" plate in the back.

Barrel: 4.8cm OD 4.2cm ID and 6m long hydraulic steel pipe that can be split in the middle for easier transport.

The only really confirmed chrony reading is with golf balls at 5x mix. It reads around 420 m/s (about 1380fps)
I have one more, it was with a 516g lead slug at 7x and it traveled 224.4m/s or 735Feet/sec. This was a relatively bad shot.


Chamber and metering setup.

Chamber connected to barrel.

Connector in the middle of the barrel, sealed with Oring.

Propane meter connected to chamber (no propane bottle connected)

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Thanks for all the help received through this forum.

Currently waiting on a exploding watermellon in slow motion .

Awwww, poor golf ball . Nice work Spudfarm.

jrrdw wrote:Currently waiting on a exploding watermellon in slow motion .

Awwww, poor golf ball . Nice work Spudfarm.

i hope i can get a melon tomorrow

well nice work might not describe it so well, it is a fairly simple design.

but it is fun!

so what do you think a slug will do to a lawnmower sized engine?

I think if it hits the lower end it with bust right through the casing then hit the crankshaft and stop with damage to the crankshaft , bust the cast iron flyweight maybe???

Try it and find out !!! Aim for the back of the block it's a flat target.

mabe the slug spilt into two pieces and make two exit holes

i think i will shoot into thee cylinder from the top and see where it goes from there

I am also going to shoot a big canister of sand with a APFSDS round to see the damage it takes.

If i feel really stupid i might try 10x right besides my own house

Dude this is a beast!!! You should def. chrony it to see what type of speeds your getting with golfballs..Did you sleeve your chamber in something beacause that dosent look like steel on the outside... but maybe thats just me being a noob Anway good video, good music...

Can you maybe add some pictures of your burst disc setup? I've been trying to find a good burst disc setup to use in a mini hybrid I've been planning for a while

theBOOM wrote:Dude this is a beast!!! You should def. chrony it to see what type of speeds your getting with golfballs..Did you sleeve your chamber in something beacause that dosent look like steel on the outside... but maybe thats just me being a noob Anway good video, good music...

Can you maybe add some pictures of your burst disc setup? I've been trying to find a good burst disc setup to use in a mini hybrid I've been planning for a while

Thank you

I do have a chrony somewhere, it's just been about a year since i last saw it so i have to look for it.

It is steel, sandblasted and painted black. it is also pressure tested to 280bar.

i remember that i made a thread about burst disk holders, that's where i posted it i think. otherwise it is a thread called "ghetto union" or something under hybrid discussion.

its really very simple. its a 2" malleable copuling with about a 1" piece of a 2" nipple in it. then there is a aluminium washer just as big as the nipple part where th burstdisk is seated, one more washer and a gasket where the brass nipple in the cannon can seal and clamp it toghether.

on a mini hybrid you might not need those washers since it has smaller surface area.


well i have decided what tomorrows test will be. I will mainly be concentrating on heavy buckshots inside casings that break open on impact and spread inside the target to make a decent exit wound on something like a microwave.
the doubt i have is in the casing and its strength and the fact that the whole thing can destroy my whole barrel.

the engine is being used in another experiment that i can't mention.

I've gone off loud music in clips so I skipped to the shot itself each time I rewatched it, I liked the sound it made ^_^

SpudFarm wrote:well i have decided what tomorrows test will be. I will mainly be concentrating on heavy buckshots inside casings that break open on impact and spread inside the target to make a decent exit wound on something like a microwave.
the doubt i have is in the casing and its strength and the fact that the whole thing can destroy my whole barrel.

A can packed solid with sand and lead shot perhaps.

Failing that you could always wind your own cardboard sabots with a roll of brown paper, some glue, a wooden dowel for the core and a wooden plug to close one end. Create partial lengthwise slits in the front section to encourage it to burst on impact.

Yeah it does make a nice sound

The problem with cans and those things are that they have to fit perfectly in the barrel, Just wrapping it with tape won't do it. it does work in a floppy way with a rag behind it but i want it to go straight

I think the cardboard might be an idea. but for now i just stick to the fast and primitive. If it does not work i will do like you said.

Thanks for the fast respond Spudfarm.. I found the thread it looks like a good idea... but I thought.. you did it beacause a normal union would cost to much.. in my case a union would cost less than 15 bucks from a hydraluics store AND it would be rated to 100+ bar pressure.. so I'll just buy one instead of making one... well thats the burst disc setup looking more promosing so far.. but there might be another burst disc setup that I haven't though of yet.. I'll keep trying to come up with one that is fast/ easy to reload and will seal airtight 100%...

theBOOM wrote:Thanks for the fast respond Spudfarm.. I found the thread it looks like a good idea... but I thought.. you did it beacause a normal union would cost to much.. in my case a union would cost less than 15 bucks from a hydraluics store AND it would be rated to 100+ bar pressure.. so I'll just buy one instead of making one... well thats the burst disc setup looking more promosing so far.. but there might be another burst disc setup that I haven't though of yet.. I'll keep trying to come up with one that is fast/ easy to reload and will seal airtight 100%...

I can't get unions in Norway at that size that is rated for any pressure.
And when ordering from USA i will get NPT threads, that's not what Norway uses.

How did you come across the pipe for the chamber? are the end caps welded on? if so, the welds are very clean.

ramses wrote:How did you come across the pipe for the chamber? are the end caps welded on? if so, the welds are very clean.

The chamber and barrel comes from Lardas shop. it has 7mm thick walls.

it is a 2" plate that was chamfered (along with the chamber) and the "cliff" formed is filled with steel and then lathed off to make a nice finish.

Very impressive Spudfarm. That chamber of yours is probably one of the cleanest and well made chamber on a hybrid I have seen in a long time (I like it as much as Larda's).
Gotta say you never disappoint, hell you brought me out of my non-posting and lurking slump on these forums.
Great job on that cannon! Looking forward to more videos.

Killjoy wrote:Very impressive Spudfarm. That chamber of yours is probably one of the cleanest and well made chamber on a hybrid I have seen in a long time (I like it as much as Larda's).
Gotta say you never disappoint, hell you brought me out of my non-posting and lurking slump on these forums.
Great job on that cannon! Looking forward to more videos.

Thank you really much!
funny you mentioned that, from the start i wantet a cannon that was clean without a ton of wires and propane tanks hanging here and there.
I think i will bring it to the other house we have and shoot it at the highest possible mix I can. probably 9x since the portable compressor limit me abit.

I may have my chrony there to so i can get som readings. It is really hard to get accurate readings when the muzzle is so close th the ground.

If i do fire buckshot i think i will film it in high speed, have allways wanted to see the muzzle blast of it in high speed. i hope there are some flames through the long barrel, but i don't think so.

I can't really promise anything because I allways want to fire at something different.

But thank you!