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Supressor Round

Post about things you have launched or thought about launching. Also post about various materials used for building cannons. No posts about explosive projectiles!
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Supressor Round

Unread postAuthor: Bias_P11 » Sat Sep 03, 2011 5:20 pm

Pros:
>This round is made up of a solid ammo and a cardboard tube tail, with slits cut in it. It can be made of any semi-flexible sheet rolled into a tube, can be any size. Only needs some tape otherwise.
>When shot, pressure can be released from these slits when the round exits the barrel, suppressing some sound. The tip can actually be just about any ammo as long as it can be attached to this.
>The back end is taped shut to prevent the slits from opening up and causing excessive drag. The suppressor round also helps stabilize rounds like a dart and can have slits cut diagonally to spin the round.
>Better than a suppressor because its not as bulky.

Cons:
>Not very effective as suppressor, only reduces the sharp "crack" sound of some spudguns.
>Labor intensive to make.
>Less performance than other darts.
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Unread postAuthor: Brian the brain » Sat Sep 03, 2011 5:44 pm

:D

An integral suppressor would not be bulky.
Neither would a captive piston...
Or a fast resetting valve...

A longer barrel would up performance and accuracy and reduce sound.
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Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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Unread postAuthor: Bias_P11 » Sat Sep 03, 2011 6:16 pm

Brian the brain wrote::D

An integral suppressor would not be bulky.
Neither would a captive piston...
Or a fast resetting valve...

A longer barrel would up performance and accuracy and reduce sound.

Are we talking pneumatics here? I use this for a combustion Mini-Medium. Suppressors are pretty bulky for mine. But yes longer barrel, integrated suppressor and other things that I don't know.
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Unread postAuthor: POLAND_SPUD » Sat Sep 03, 2011 6:17 pm

a captive piston...

[youtube]http://www.youtube.com/watch?v=izRvFkCbnTg[/youtube]


I don't think I've seen this posted on SF, have you ?

ohh and I haven't seen this ->
[youtube]http://www.youtube.com/watch?v=yMJSwd0nnq0&feature=channel_video_title[/youtube]
Is he on SF ?
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Unread postAuthor: Bias_P11 » Sat Sep 03, 2011 7:17 pm

Uh.... uhmm. Those look a bit complicated for me. and rather integrated.
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Unread postAuthor: POLAND_SPUD » Sat Sep 03, 2011 7:47 pm

a captive piston is just a sabot that travels with the round along the barrel and then is stopped at the muzzle.... therby trapping the gases
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Unread postAuthor: Bias_P11 » Sat Sep 03, 2011 8:11 pm

POLAND_SPUD wrote:a captive piston is just a sabot that travels with the round along the barrel and then is stopped at the muzzle.... therby trapping the gases


Kinda..... hard to do with PVC isn't it? Cool tho.
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Unread postAuthor: POLAND_SPUD » Sat Sep 03, 2011 8:15 pm

As you probably understand the problem here is that the captive piston has to be stopped almost instantly at the muzzle... this means there is a lot of stress acting on the barrel, the muzzle attachment designed to trap the piston and the captive piston itself

This method has one additional disadvantage - the piston has weight so it reduces the performance of the gun
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Unread postAuthor: Bias_P11 » Sat Sep 03, 2011 8:45 pm

POLAND_SPUD wrote:As you probably understand the problem here is that the captive piston has to be stopped almost instantly at the muzzle... this means there is a lot of stress acting on the barrel, the muzzle attachment designed to trap the piston and the captive piston itself

This method has one additional disadvantage - the piston has weight so it reduces the performance of the gun

Yup. could definitely do this with a pneumatic bbgun sometime tho
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Unread postAuthor: warhead052 » Sat Sep 03, 2011 9:01 pm

POLAND_SPUD wrote:
a captive piston...

[youtube]http://www.youtube.com/watch?v=izRvFkCbnTg[/youtube]


I don't think I've seen this posted on SF, have you ?

ohh and I haven't seen this ->
[youtube]http://www.youtube.com/watch?v=yMJSwd0nnq0&feature=channel_video_title[/youtube]
Is he on SF ?


His name is Spudamine.
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Unread postAuthor: jackssmirkingrevenge » Sun Sep 04, 2011 12:49 am

Bias, your user icon is reminding me ofwork, on a blessed Sunday!

As to your idea, couldn't you have exactly the same effect just by using a normal round and cutting some slits in the barrel at the muzzle end?

POLAND_SPUD wrote:I don't think I've seen this posted on SF, have you ?


Here

As you probably understand the problem here is that the captive piston has to be stopped almost instantly at the muzzle... this means there is a lot of stress acting on the barrel, the muzzle attachment designed to trap the piston and the captive piston itself


The critical factor is keeping piston weight down to reduce stress on the system, this means keeping the diameter very close to the pojectile and making it out of relatively soft and low density material like UHMWPE. A sabot for a 6mm projectile would weigh less than an airsoft BB.

It's also useful to use a heavyweight projectile, this gives high muzzle energy without very high velocity, which again keeps the sabot impact force down.

This method has one additional disadvantage - the piston has weight so it reduces the performance of the gun


... but it also increases diameter compared to the projectile, which increases base area and therefore available energy, and if you're using UHMWPE you're increasing diameter without an untoward increase in weight.

What you want is something like this:
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Unread postAuthor: jackssmirkingrevenge » Tue Dec 06, 2011 3:22 am

Interesting related development for firearms, not sure how effective it would be in practice.
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Unread postAuthor: dewey-1 » Tue Dec 06, 2011 9:14 am

JSR;

At first glance, I thought you were showing off new parts that you just made with your new machining skills! :)

Possibly could be redesigned to make a whistling projectile.
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Unread postAuthor: Brian the brain » Tue Dec 06, 2011 2:44 pm

I'd say they could whistle as is....


About the captive piston: The piston doen't need to stop abrubtly as long as the ammo isn't jammed into or onto it and has enough mass to keep going.

An aircushion would work, so would a spring or perhaps an internal wire with spring attached would be better.
That would allow use of ammo the full barrel diameter.

I imagine a big plug in the back of the chamber of a combustion cannon attached to the sabot with a wire serving as a damper.

We could try all sorts of things and see wich holds up best.
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Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!

Can't ask for a better compliment!!
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Unread postAuthor: al-xg » Tue Dec 06, 2011 3:16 pm

A bit of a silly idea ? surely its not more practical or cost effective to machine each bullet instead of just machining one muzzle break.

Nice projectiles though!
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