3042 Cubic Inch Hybrid WORKS!

Harness the power of precision mixtures of pressurized flammable vapor. Safety first! These are advanced potato guns - not for the beginner.
User avatar
Fnord
First Sergeant 2
First Sergeant 2
Posts: 2239
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Been thanked: 1 time
Contact:

Sat Oct 29, 2011 11:44 pm

Quite a sustained boom you've got there. Even that 2" port seems to take a while to vent.

Also, I like how you didn't waste any time getting this thing together.
Slackers such as myself seem to be dominating the forum as of late :)

And I'm assuming that poor pressure gauge is now dead.
Image
User avatar
Technician1002
Captain
Captain
Posts: 5189
Joined: Sat Apr 04, 2009 11:10 am

Sat Oct 29, 2011 11:57 pm

jackssmirkingrevenge wrote: surprised it didn't loop around the tree, nicely done :)
The thing weighs over half my weight. Can you imagine holding on to it when it is fired. It would give you quite a toss. Add a barrel and projectile and that would be a serious kick.
CooperJS
Private 4
Private 4
Posts: 81
Joined: Sun Sep 18, 2011 4:20 am

Sun Oct 30, 2011 12:59 am

would be amazing to make it look like this

Image
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Sun Oct 30, 2011 1:48 am

Technician1002 wrote:The thing weighs over half my weight. Can you imagine holding on to it when it is fired. It would give you quite a toss. Add a barrel and projectile and that would be a serious kick.
I was thinking of trying out this pendulum setup with my piston hybrid just for entertainment/a reason to shoot the gun. At a 10x mix, HGDT reckons it would have a similar performance with Dornep's cannon at a 3x (assuming the barrels and projectiles are the same and taking in to account HGDT's lack of ability to model piston valves). Considering my cannon weighs about 1/4 what this cannons weighs, it would have the same momentum but higher recoil velocity and energy due to the similar performance but lighter cannon.

Does that transfer directly in to this practical scenario where if I replicated Dornep's video, my cannon would swing more violently upon firing or have I wagged* one too many physics lessons at high school?

Part of the reason I'm asking was because I was thinking about recoil when firing the MiniBoy and what it would compare to. For example, the recoil velocity of a .500 S&W Magnum is about 9m/s and energy about 60J whereas with a 150g projectile at a 10x mix, the piston hybrid gives figures of about 3m/s and 80J. That doesn't sound like a whole much more and is probably more easily dealt with considering the recoil for the cannon is 'slow' compared to the S&W's 'sharp' recoil and the fact I have a recoil bar to help distribute the force.

I'm usually terrible at the physics of firearms so things like this I feel I should check with people who know what they're doing.

Dornep, I've strung cannons up before to paint them, never had the idea to actually fire one when it's like that. Cool idea :wink:


*skipped, cut, not attended
User avatar
Dornep
Specialist
Specialist
Posts: 151
Joined: Thu Aug 09, 2007 5:49 pm
Location: Florida

Sun Oct 30, 2011 11:25 am

Thanks for the replies guys.

The next hurdle will be the barrel.

I want at least a 2" x 20' barrel that...

1. Won't Sag
2. Won't whip back and forth and snap off the union when fired
3. Can be broken down into 10' sections
4. Doesn't weight a 1000lbs
5. Doesn't cost a $1000

:shock: hmmm
Image
User avatar
saefroch
Staff Sergeant 2
Staff Sergeant 2
Posts: 1679
Joined: Mon Jun 08, 2009 8:47 am
Location: U.S.A.- See Map

Sun Oct 30, 2011 11:44 am

McMaster-Carr item numbers 48855K16 and 6803K17 both fit the bill if you find a good way to connect two of them. You'll require a barrel support no matter what you use.
User avatar
jrrdw
Moderator
Moderator
United States of America
Posts: 6571
Joined: Wed Nov 16, 2005 5:11 pm
Location: Maryland
Has thanked: 39 times
Been thanked: 22 times
Contact:

Donating Members

Sun Oct 30, 2011 12:22 pm

2. Won't whip back and forth and snap off the union when fired
It will all have to recoil as one to keep that noise down, even then it's a tall order...

A lot of bracing???????
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 321 times

Donating Members

Sun Oct 30, 2011 12:24 pm

jrrdw wrote:A lot of bracing???????
Image

Inspiration ;)
hectmarr wrote:You have to make many weapons, because this field is long and short life
User avatar
Moonbogg
Staff Sergeant 3
Staff Sergeant 3
United States of America
Posts: 1731
Joined: Mon Oct 13, 2008 10:20 pm
Location: SoCal
Has thanked: 153 times
Been thanked: 100 times

Sun Oct 30, 2011 4:00 pm

Dornep wrote:Thanks for the replies guys.

The next hurdle will be the barrel.

I want at least a 2" x 20' barrel that...

1. Won't Sag
2. Won't whip back and forth and snap off the union when fired
3. Can be broken down into 10' sections
4. Doesn't weight a 1000lbs
5. Doesn't cost a $1000

:shock: hmmm
That thing is a true beast. As far as supporting a 20' barrel, thats going to be a project. Have a look at FEAR (a cannon on this site) I can't find the link to it, but its a huge hybrid kind of like yours with like a mile long barrel. I don't remember even seeing a lot of bracing on his barrel, but go have a look in the showcase or maybe someone will link it. Nice work.
User avatar
mobile chernobyl
Corporal 3
Corporal 3
United States of America
Posts: 756
Joined: Sun Dec 03, 2006 11:53 am
Been thanked: 7 times

Sun Oct 30, 2011 4:21 pm

I think he doesn't have a lot of bracing, because he uses supports from the ground to prop up his barrel - it would be very "noodley" without such a support.
User avatar
Dornep
Specialist
Specialist
Posts: 151
Joined: Thu Aug 09, 2007 5:49 pm
Location: Florida

Sun Oct 30, 2011 7:47 pm

Jack.. that picture is exactly the nightmare that comes to mind when I think of raising the barrel into the air on this thing....

I remember seeing the FEAR cannon back in the day before I went AWOL from the site.. To me... his cannon is more of an 88mm flat shooting tank killer while I'm hoping mine will be more like the Paris Gun above... lol

I have an idea of using turnbuckles that i can tighten attached to cables going to the barrel to add support and make a tight barrel seal between the two sections..
Image
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Sun Oct 30, 2011 8:06 pm

Dornep wrote:I remember seeing the FEAR cannon back in the day before I went AWOL from the site.. To me... his cannon is more of an 88mm flat shooting tank killer while I'm hoping mine will be more like the Paris Gun above... lol
To be fair, FEAR had a 50' barrel and I know it was at least tested at 10x mixes (not sure whether it ever fired something at that mix) whereas this will have a barrel half the length and operate at much lower mixes (although it is twice the volume). Your cannon could probably just out-perform it at low mixes but FEAR leaves this in the dust if it decides to go up to 10x mixes. :wink:
User avatar
Lockednloaded
Staff Sergeant
Staff Sergeant
United States of America
Posts: 1566
Joined: Thu Sep 03, 2009 9:38 pm
Location: Texas, USA
Been thanked: 6 times

Sun Oct 30, 2011 8:25 pm

Wow.

Love the power and sustained combustion, you could probably hook it up to a Vogt pattern loader for full auto
I love lamp
User avatar
Fnord
First Sergeant 2
First Sergeant 2
Posts: 2239
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Been thanked: 1 time
Contact:

Sun Oct 30, 2011 9:13 pm

If you can get a hold of a section of this stuff, you'll have most of the work of making a barrel support done for you already. Even steel antenna towers are fairly light for their size.
Attachments
30AMERTOW-SPC_zoom.jpg
30AMERTOW-SPC_zoom.jpg (33.09 KiB) Viewed 2913 times
Image
User avatar
POLAND_SPUD
Captain
Captain
Posts: 5402
Joined: Sat Oct 13, 2007 4:43 pm
Been thanked: 1 time

Sun Oct 30, 2011 10:27 pm

Even that 2" port seems to take a while to vent
yeah it begs for a 4" port :D

I guess that would make sense... since you're limited to low mixes it would make sense to make the barrel as large as possible...

bigger barrel = greater barrel volume = quieter gun

Plus it doesn't mean you're limited to big heavy and slow ammo only... With saboted ammo you could lob rounds 1.5 miles away
you see JSR I wrote sabots... that's right now you've got to agree with me : D


ohh and before you decide to put a long barrel on it check with HGDT if it makes any sense at all
Children are the future

unless we stop them now
Post Reply