23 replies to this topic

[Zer]

Well I've read through these forums for a couple years now, but this will be my first post.

Recently I got back into Nerf with the advent of the Vulcan. One of my friends got one, and it all went crazy after that. Now our arsenal includes 9 magstrikes, 1 longshot, 1 recon, 2 vulcans, and my trusty lock and load.

We also got our hands on an electric shopping cart and it's currently being "uparmored" with cardboard. Knowing that I'd have to defeat this shopping cart o doom, I set about creating a bazooka.



My Vulcan is next to it for a size reference.



"Cartridge" and mini nerf football "rocket."



Closeup of receiver with rear cover open



Cartridge locked in place, rear cover open.

The barrel is 2" PVC, the receiver is made from a 2" PVC coupler with locking lug recesses cut into it. I nested it within a 3" ABS pipe by heating quartered 1/2" PVC with a torch and rolling it around with a 2" coupler to flatten and shape it so it would fit snugly.

The "cartridge" is made of (from left to right in the 2nd pic):
2" to 1" bushing
screws with cut heads for lucking lugs
1" coupler
2" to 1" bushing
2" PVC expansion chamber
2" endcap
1/4" NPT male fitting with a female/female coupler screwed onto it from the inside

Currently it runs off of my air compressor, but the parts to run it off of Co2 cartridges are coming in the mail. Using a piece of packing tape inside the coupler has reliably fired the bazooka at 90-100 PSI. Range is unknown, as I've only fired it in my garage. Paint is Rustoleum Camo Khaki, Rustoleum Camo Brown, and Krylon flat black.

The ideal projectile for it is the Nerf vortex pocket football, but it will also shoot ballistic balls.

It's my first "home made" so I'll have my flame shield ready.

Edited by Zer, 15 December 2008 - 01:15 AM.

[Tornado13]

HOLY FUCK! THAT THING IS A BEAST! Really though this has no point except for the awe factor and maybe for scenario play. It was cool that you created it though. All in all that is pretty awesome.

EDIT: Congrats on the first post! Very clean!

Edited by Tornado13, 15 December 2008 - 12:53 AM.

[stickfigure91x]

We also got our hands on an electric shopping cart and it's currently being "uparmored" with cardboard. Knowing that I'd have to defeat this shopping cart o doom, I set about creating a bazooka.

Anyone else get the image of some fat guy in a rascal at the super market getting seriously owned with this?

[Zer]

HOLY FUCK! THAT THING IS A BEAST! Really though this has no point except for the awe factor and maybe for scenario play. It was cool that you created it though. All in all that is pretty awesome.

EDIT: Congrats on the first post! Very clean!

It is for scenario play, and it is a beast. It's a little over 6' long.

Anyone else get the image of some fat guy in a rascal at the super market getting seriously owned with this?

That's one of the images that inspired me to make it.

[cheesypiza001]

HOLY CRAP
That think is insanely huge. How much does it weigh when fully loaded?

[Radio]

Ive been WAITING for some one to make a gun that shoots these things. does anyone know how much of a difference the fins make?

[Zer]

HOLY CRAP
That think is insanely huge. How much does it weigh when fully loaded?

It's mostly hollow... so maybe 15 pounds. The "cartridge" weighs about 4 by itself.

Ive been WAITING for some one to make a gun that shoots these things. does anyone know how much of a difference the fins make?

The fins hold it tightly into the receiver until you lock in the cartridge, and the camming action pushes the football forward tightly into the barrel.

[eddieoctane]

Anyone else get the image of some fat guy in a rascal at the super market getting seriously owned with this?

I am. But I'd rather nail one of the football players at Penn State who get a scooter thing whenever they stub their toe because god forbid the football team should ever have to walk anywhere with a hurt little toe.

How is that thing actually fired? Is that massive PVC insert an air tank or what? The idea of having 2-3 extra "rockets" on my back as I shoot this thing at people appeals to my inner sadist.


As for the fins, I would assume they make a huge difference in stabilizing the flight of the football. Anyone who has thrown a regular football and a vortex one can usually get the Vortex to go much, much further. Without the fins, I'd wager that it would fly more like a potato cannon. Plus, the wins make it more like a real rocket, just to appeal to the inner geek in us.

[Zer]

How is that thing actually fired? Is that massive PVC insert an air tank or what? The idea of having 2-3 extra "rockets" on my back as I shoot this thing at people appeals to my inner sadist.

It is currently fired from my air compressor. I'm waiting on some fittings and parts to arrive to hook up a 12gram based co2 system.

That PVC bit that goes in the end of it is an expansion tank. the coupler on it unscrews, and you put a piece of ordinary packing tape in there, and close it up. Apply air pressure, and as soon as the tape ruptures from the pressure build up, it shoots. It is a little slow to reload, and realistically will shoot one round per minute.

EDIT:

Just got the latest bits to make it all work... its a chain of adapters that runs off a CO2 bike tire inflator. Off the CO2 tire inflator it goes: 1/16 NPT threaded chunk, 1/16 to 1/8 npt adapter, then 1/8 to 1/4, then a female female 1/4 NPT coupler and finally a 1/4npt to barbed fitting. Did a test fire of the system and the co2 cartridges can fire it.

I'm not sure how many rounds I'll get out of a 12 or 16g cartridge. I don't have a good area to test it. Soon I'll integrate the co2 system onto the gun. The air hose for it is stretching/straightening out in my garage right now.

Edited by Zer, 16 December 2008 - 12:31 AM.

[silentsnipe]

Here is something that's kinda like what you're talking about.

[zadjii]

I can't possibly be the only one repetitively chanting "WRITE-UP! WRITE-UP!" can I? I love the idea of scenario nerf, even though a lot of people here don't usually appear to. I was going to make something like this for physics class and we were going to have fights trying to hit the other teams target, but this, this is SO much better.

[Zer]

I can't possibly be the only one repetitively chanting "WRITE-UP! WRITE-UP!" can I? I love the idea of scenario nerf, even though a lot of people here don't usually appear to. I was going to make something like this for physics class and we were going to have fights trying to hit the other teams target, but this, this is SO much better.

The best I can do at this point is a CAD drawing

For a simple target gun you can use a bike pump and inline sprinkler valve type setup. Easy to do and much more reliable and efficient than a ball valve. Feel free to PM me for more info.

Here is something that's kinda like what you're talking about.

It uses the same projectiles but operates on a completely different concept. I wanted mine to require a two-man crew and a significant downtime for reload. That video does show a really interesting design capable of a very good ROF. That gun in the video utilizes a valved system, whereas mine utilizes a disk of material that ruptures at a fairly consistent PSI.


--------UPDATE---------

Finally range tested the gun. At about a 40 degree angle it shot 145 yards. It gets one shot per 16 gram co2 with a little left over, so I'm thinking a 12 gram will work just fine. Firing/pressurizing delay is about half a second.

Edited by Zer, 19 December 2008 - 11:49 PM.

[Ner Commando]

Holy poop that thing is GINORMOUS. I would not want to be shot at with that thing. That is one sick gun.

[Arconious]

Isn't CO2 a big problem for plastics though? The low temperatures that are required to make it work cause the plastic to become brittle. Which would cause premature breakage of the gun. Anything with that much work into it would be a pain to replace. A normal paintball air tank would probably be better for the gun. You might want to check with somebody a bit more experienced, but I'm just letting you know it is a possibility.

[death by cheez]

Nice gun, but curse you! I was going to go and get some parts for my doom cannon tomorrow. Though I never thought of using shells... interesting idea.

[Zer]

Isn't CO2 a big problem for plastics though? The low temperatures that are required to make it work cause the plastic to become brittle. Which would cause premature breakage of the gun. Anything with that much work into it would be a pain to replace. A normal paintball air tank would probably be better for the gun. You might want to check with somebody a bit more experienced, but I'm just letting you know it is a possibility.

The operating pressure of this cannon is about 100 PSI, which is about a third of what the PVC is rated to. The temperature issue is neglible due to the extremely brief exposure to the CO2. It sees less than half a second of exposure to gaseous CO2, and the length of tubing running up to the burst disk is plenty of room to allow for sublimation if any solid particles of co2 tried to make their way into the PVC section.

The small co2 cartridges I use are only good for one shot because they are rapidly dumped of all gaseous co2. If I left it hooked up and allowed for the entire solid contents to sublime (by somehow leaving the trigger system "on" and keeping the burst disk from breaking), that phase change would result in temperatures about 75* below freezing. PVC exposed to that temperature would become quite brittle.

[Arconious]

I wasn't worried about the air pressure, PVC can withstand quite a bit of pressure. I suppose you are right, but even brief exposures to the temperature of the CO2 is likely to reduce some of the durability of the gun. Probably not very noticeable. Especially if you have it mounted. But eh, I haven't dealt with CO2 very much.

[Grenada]

Was I the only one who thought, and I quote "OMFG, a panzerschrek." Add the face guard, and you have something which would like pretty dang alike. Good paint job too

Seriously, I need to make me one of these things. One of my friends is making a small nerf AFV, and I need something to punch through cardboard

Question:How did you get that awsome paint job?

Edited by Grenada, 27 February 2009 - 09:48 PM.

[Nerf Bros]

Was I the only one who thought, and I quote "OMFG, a panzerschrek."

No you are not... that's exactly what i thought, making it into a panzerschrek would look so awesome. You should make a video of you shooting it. I want to see that baby in action.

-nerfbros

[Kid Flash]

This topic was pretty old. Try to refrain from posting in 1 moth or older topics... Sorry for the backseat mod.

[Robonerfer1]

Wow, that's awesome.
The way it loads reminds me of the rocket from Halo.

[astooo]

it relly cool but how do you shoot it and whats the point of haveing it when you only have 1 shot then you have to go back to a air compresser. but still cool

[Talio]

I guess someone has been approving new members. Well might as well do my part. He's been banned.

[PVC Arsenal 17]

Edit: Deleted. Delete this post please. I had a comment to make, and afterwards thought it better not to make it.

Edited by PVC Arsenal 17, 19 January 2010 - 10:24 PM.