Possible way to achieve a "shotgun" effect

[zvallance1]

Well, heres an idea i've had floating through my head for the longest time..a relatively easy way to fire multiple small objects, (or one object that's just too small to fit nicely in your barrel) at once.

<img src="http://img159.imageshack.us/img159/1609 ... dea3uc.jpg">


the idea itself it pretty straightforeward, so i'll be brief about this..
1. get the largest endcap that you can, that will fit snugly INSIDE your barrel.
2. using a hacksaw/dremel/your tool of choice, remove a small section of your barrel, about 4 inches from the end of the barrel (this hole is to allow the excess air pressure to be realeased, so that extra pressure it not put on the endcap.
3. cut off a small length of whatever size PVC fits snugly inside your barrel, and glue it to the inside of the end of your barrel
4. (optional) attach some sort of cushion to the bottom of the PVC section you installed in step 3, to cushion the endcap (and reduce wear-and-tear) when it flies into that little bit of PVC.
5. Load with your favorite ammo that you have been previously unable to use, and shoot!

Note -
- this will severly decrease the accuracy of this barrel at anything but close to moderate range, but should effectively provide a "spread" of ammo.
- if you do do this with your barrel, be warned that you wont be able to undo it, so be sure that you are prepared to have a dedicated shotgun barrel before you attempt this

have fun,
zev

edit: how embarrasing, i forgot to inclue the picture!

[iamthewalrus]

im thinkin that would be very dangerous, that might work for combustions, but i would never put that much restriction on a pnumatic or a hybrid, come to think o fit i wouldnt try it on a combustion either. i think u would get the effect of having something jammed into the end of a rifle, because in essence u just blocking the main exit of the pressure and reducing it to a little cut in the end of the barrel.

[zvallance1]

i think u would get the effect of having something jammed into the end of a rifle, because in essence u just blocking the main exit of the pressure and reducing it to a little cut in the end of the barrel.

Well, as long at the hole you make isnt too small... maybe 2/3 of the barrel's actuall width, it should work...
i mean, when you put normal ammo in your barrel you literally ARE "getting the effect of having something jammed into the end of a rifle" the only difference here is that the exit is slightly smaller...

In further defense to my idea... just take a look at the "spudchucker 1"
That cannon was equipped with a pnuematic ram so that the ball valve used in the cannon could be opened at an acceptable speed.

<img src="http://leckemby.net/spudwerx/piston1.jpg">

Now, correct me if I'm wrong, but the way i see it...my idea is just taking that pnuematic ram one step further, and by increasing the opening that the excess air will come out of, i've made it even safer =)

-zev

[boilingleadbath]

Restriction smestriction.
Your real concern should be the relitivly massive piston hitting the stop at a few hundred feet/sec, which will either shatter the pipe in a rather impressive manner, or simply "eject" the stop ring.

[zvallance1]

4. (optional) attach some sort of cushion to the bottom of the PVC section you installed in step 3, to cushion the endcap (and reduce wear-and-tear) when it flies into that little bit of PVC.

i did mention that somehting to handle that shock would be a nice touch =)
you're probably right though...the impact might be a little TOO much for either the barrel or the endcap..

oh well...it was a good idea while it lasted, ill probably get around to trying it on a small scale later, and maybe it will work as i hoped.

[Atlantis]

Two things.
1: If you wanted to switch between shotgun/regular barrels, just have the end stopper be able to be screwed off the end.
2: Build a spring into the stopper or onto the shell, it should slow the shell down but the ammo will keep going at high speeds. You could also build a permanent stopper on the end and have a spring stopper that hits the shell, this would make a spring buffer more durable.

[HAYLO_Stealer]

if you put o ring on the part that hits the barrel the impact would be greatly decreased.

[zvallance1]

2: Build a spring into the stopper or onto the shell, it should
slow the shell down but the ammo will keep going at high speeds. You could also build a permanent stopper on the end and have a spring stopper that hits the shell, this would make a spring buffer more durable.

thats probably the best idea i've heard in quite some time now...
A bedspring attatched to the stopper at the very end of the barrel, would definatly (sp?) be of use..
I also spoke with my friend's dad last night...he's an engineer at a company that develops missiles, commercial aircraft, and the like...And one of the things he specializes in is acoustics, or more specifically the damage that high-speed vibration can have on electronics, and how to protect them..
Anyways, he said that he might be able to dig up some used "shock-absorbing foam"

As far as i can tell,its something along the lines of the Tempurpedic matresses, which can absorb the shock of someone jumping onto the bed, and then spring back to exactly how it was, once the pressure is taken off it...Think that, but it'll 20x more effective, and shock-absorbant.

man, im thinking this will be a fun project!

[Atlantis]

You may need to be careful with any kind of foam, it might be flammable. Also, the foam might squish around the edges of the shell jamming it. Springs would proably be easier, add a small chunk of a coulper the same size as the shell, this will give it an even surface to absorb the impact. Good luck!

[zvallance1]

well...im not entirely sure if springs alone would be enough...it would have to be a pretty stiff spring for it alone to absorb the impact...
im thinking i'm going to try and do it with two bedspring...
have one expoxied to the end cap on the inside, and the the other epoxied to the little bit of pipe on the inside at the top,

Maybe even stick a second bit of pipe on the other end of the spring attached to the endcap, to keep the two springs from get tangled, sort of like this
[[|===========||
endcap ---spring --- bit of pipe

[taterjim]

when I want to shoot small objects ,several at a time ,I first put in a slice of wooden dowell or a thin slice of potatoe ,then the objects.usually marbles or paintballs ,then another slice of potatoe or styrofoam to hold it in the barrel. I do this in combustion or pneumatic cannons. Sometimes you have to give it time to bleed off some trapped air as you ram the ammo down the barrel..
Using this technique I have blasted multiple holes in plywood with a single shot.

[zvallance1]

when I want to shoot small objects ,several at a time ,I first put in a slice of wooden dowell or a thin slice of potatoe ,then the objects.

yeah, i personally use a rolled up sock, with a sort of tail on it...everything else shoots out, but the sock only goes about 20 feet...
This topic was just an idea to improve on the idea =)

[feral_patriot]

put whatever "shot" you're wanting to spread out in a sandwhic baggy,shove gently down barrel , then place a coarse sheet-metal screw some deemed appropriate place down the barrel towards the end to catch & shred the bag on its way out .Perhaps some wadding before the package...

[Atlantis]

I have an idea. Connect a bungee cord to the shell and the back of the chamber, that might absorb enough.

[zvallance1]

put whatever "shot" you're wanting to spread out in a sandwhic baggy,shove gently down barrel , then place a coarse sheet-metal screw some deemed appropriate place down the barrel towards the end to catch & shred the bag on its way out .Perhaps some wadding before the package...

Feral, your idea is good and all, but the purpose of this topic was to figure out an easy, and cheap way to get that shotgun feel for your gun...something that you can just pour your ammo into, pump the gun up, and let it fly...rinse and repeat as needed 8)

I have an idea. Connect a bungee cord to the shell and the back of the chamber, that might absorb enough.

This too, is a great idea, but since I really only use pnuematics, id have to worry about having an endcap smashing my $15+ valve when it shoots back :-\