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Posted: Wed Jun 18, 2008 3:55 pm
by trollhameran
I really like this design, its so simple yet so effective
Posted: Wed Jun 18, 2008 4:47 pm
by SNDM
Im sorry, but Im really dumb right now.
How exactly does it work?
Diagramss?
How do you trigger it?
Posted: Wed Jun 18, 2008 4:58 pm
by TwitchTheAussie
He mainly uses just air pressure to trigger the disks, I'm assuming.
Posted: Wed Jun 18, 2008 6:07 pm
by Mr.Sandman
im going to make one of these with a mechanical burst disk breaker thingy

Posted: Wed Jun 18, 2008 9:51 pm
by Coodude26
I just finished my burst disk cartridge design yesterday and I finished it today
Mind revising that?
Posted: Wed Jun 18, 2008 10:25 pm
by Maniac
just finished my burst disk cartridge design yesterday and I finished it today
AH HA that evil google again it confusing us.
Back on topic can you show us some pics of thins furniture and stock would love to see it.
Posted: Thu Jun 19, 2008 2:07 am
by Davidvaini
I fixed the wording on my first post.
I also got some good footage of it firing a NERF foam ball typically used in airsoft.
[youtube][/youtube]
it shows me loading a shell and firing it without separate video clips.
Posted: Thu Jun 19, 2008 3:02 am
by ghostman01
hmm thats quite loud ! are you going to use shells loaded with bb's or are you going to stick to foam balls ?
Posted: Thu Jun 19, 2008 7:59 am
by ImHUGEnJAPAN
This is a pretty cool idea and it looks inexpensive to make. When you preload these with air how much pressure will that tape hold? I would love to make one of these to shoot paint grenades or a grape shot out of 2" pipe.
I know this is simple and I understand the construction aspect, but I have a few questions.
I the first video you loaded the wadding half way down the pipe, BB's, tape, and coupling. I'm assuming you just pressurize the chamber until the tape bursts, correct?
In the second, video you just put tape over the pipe, then coupling, and then put the nerf ball in the coupling. It looks like you pressed something to burst the disk or did you just use air pressure again?
Why the two different loading methods? I assume it works the same way one just holds the BB's Better.
You said you have a bolt that slides back to break the tape. How does this not get in the way and I can't see any bolt in the videos.
Posted: Thu Jun 19, 2008 12:43 pm
by Davidvaini
the bolt version is not in the videos, I made one a while back and lost it in a box while moving. The bolt is actually a very thin curved peice of metal attached to a small handle or bolt that is on the coupling. You simply slide it back and it pierces the disk.My guess for 1.25" shells can hold around 60 psi. If you find the tape you get doesnt hold that much you can always add more layers.
As far as pressure it varies for the size of the cartridge. That is why I am simply going to use a co2 inflator. That way it fills almost instantly and bursts almost instantly and is portable and cheap.
The shells are really cheap to make. I went to a midas and a local tire repair shop and I got like 100 shreader valves free for a "school project" and then I went to Menards and got a cap for like 25 cents a coupling for around 30 cents and a 5foot pipe for around $2.00. With that 5 foot pipe I can make about 11 shells. So to make 11 shells it would cost around 8.00 or around 6.00 if you buy contractor bags.
I will have different shells for different matches. I will have some bb loaded shells and some foam loaded shells. Mainly BB shells because they are extremely effective.
Posted: Thu Jun 19, 2008 1:45 pm
by Hailfire753
Wow, this is really neat. I could definitely see this attached to the bottom of a air-soft gun as a grenade launcher.
From what I understand, the bbs are behind the burst disk? Would that not work for paintballs, as they would be crushed by the pressure?
Posted: Thu Jun 19, 2008 1:52 pm
by Davidvaini
I have not done any testing on paintballs. and yes the BB's are behind the burst disk.
Posted: Thu Jun 19, 2008 2:11 pm
by ImHUGEnJAPAN
Hailfire753 wrote:Wow, this is really neat. I could definitely see this attached to the bottom of a air-soft gun as a grenade launcher.
From what I understand, the bbs are behind the burst disk? Would that not work for paintballs, as they would be crushed by the pressure?
High pressure shreads paintballs. I was experimenting last night with my cannon. I took a toilet paper roll and taped one end shut. I put some toilet paper in the bottom to help cushion the paintballs. @90 psi with 15 paintballs I now have a giant Wagner......lol. The paintballs were obliterated when they left the barrel. I think three or four made it into the trees. I have no Idea how fast they were going.
Grape shot is very difficult to chrono. My first attempt trying to chrono a grape shot at the paintball field I play was not successfull. However we did manage @90 psi to chrono the sabot (toilet paper roll) at 168 FPS......The paint was shreaded.
These burst disk might work better at lower pressure with a shorter barrel. I'm going to make one and try it. Hell, for less than $10 why not. I think these could be great for a pod sized paint grenade launcher I could hold in my pod pack.
When you peirce the disk how big does the hole need to be? Will a small hole do it? Can you pierce it anywhere or is the center the best?
Posted: Thu Jun 19, 2008 2:32 pm
by judgment_arms
Looks good, I do believe that I’ll have to try this, particularly since I have everything but the aluminum tape.
…humm… I just had an idea…
ImHUGEnJAPAN, he doesn’t pierce the burst disk, he simply fills it up till it blows.

Posted: Thu Jun 19, 2008 2:47 pm
by ImHUGEnJAPAN
judgment_arms wrote:Looks good, I do believe that I’ll have to try this, particularly since I have everything but the aluminum tape.
…humm… I just had an idea…
ImHUGEnJAPAN, he doesn’t pierce the burst disk, he simply fills it up till it blows.

Correct.
He also had another design that did pierce the disk, but he lost it
