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Posted: Thu Dec 11, 2008 2:44 pm
by Ragnarok
Lentamentalisk wrote:If you make your suppressor that extends backwards only be on the top 3/4 of the pipe (so as to avoid the chamber) then you could extend it almost all the way back.
On big problem with that - it's meant to be removable. How will it be fitted to the muzzle? Neither a twist lock or a threaded connection would allow that.

The other thing is that these fittings need to double for both the breech load and semi-auto configurations. The breech load barrel is twisted through 90 degrees to unlock it - the suppressor, being fitted to the barrel, will twist with it, crashing into the chamber.

For those reasons, the suppressor cannot extend back past the end of the chamber.
ALIHISGREAT wrote:and i would just use a threaded fitting instead of 'twist lock' so weight isn't much of a problem.
"You would" being the important term.

Personally, when I've looked into it before, I find threaded fittings like that on the muzzle pretty ugly.

Aside from the higher practicality of the twist lock, it taking me no longer than an instant to change over two fittings (it being a mere quarter twist to fit them), such as the porting, suppressor or muzzle brake - if I'm using more weight than the twist lock can with stand, it's already too much, because it's creating an unnecessarily large moment on the barrel.

Even disregarding that, I have several attachments already which use the twist lock which I don't want to throw away.

@JSR: It's not really a line of sight issue (although obviously I don't want a problem in that area) - it's a weight one.

Taking things into account, and with a looped-back moderator, I think I can manage a suppressor of a volume of about 1200 cc, a little more than the combined volume of chamber and barrel.
This isn't a truly appalling volume, but it's not exactly huge when you're trying to quieten down around 23 litres of air all trying to escape the muzzle at the same time. (Interesting trivia - this actually means that 3vo uses roughly twice as much mass of air as the mass of powder in a .50 BMG round)
In a theoretical flow ideal, that means I can drop the pressure at the muzzle to as low as 6 bar. There's still a lot of gas volume, but I suspect I can reduce the sound considerably.

Still, I'm still trying to find ways to make this volume count for more.

Oh, and with regards material, I'll be making it from PVC sheet.

EDIT: Spelling.

Posted: Thu Dec 11, 2008 3:58 pm
by jackssmirkingrevenge
_________
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Something like this?

Posted: Thu Dec 11, 2008 4:05 pm
by ALIHISGREAT
hmm I never considered a looped-suppressor... if i even get round to making a hybrid....

with your configuration rag, you could make a huge one, running either side of the barrel, but then again, it may not be worth it because the performance depends on how well you can 'strip' the air off.

Posted: Thu Dec 11, 2008 4:10 pm
by POLAND_SPUD
now why don't you put a bv that would allow you to cut chamber volume to silence the gun? you don't need the higher power every time

Posted: Thu Dec 11, 2008 4:14 pm
by ALIHISGREAT
POLAND_SPUD wrote:now why don't you put a bv that would allow you to cut chamber volume to silence the gun? you don't need the higher power every time
or you could just lower the pressure :wink:

Posted: Thu Dec 11, 2008 4:42 pm
by POLAND_SPUD
I realized something... he is planining to use a slide valve for piloting (which can't be silenced) so he can't silence the gun anyway

Posted: Thu Dec 11, 2008 4:45 pm
by ALIHISGREAT
POLAND_SPUD wrote:I realized something... he is planining to use a slide valve for piloting (which can't be silenced) so he can't silence the gun anyway
and then there is the QEV exhaust too.... but i still think it will be worth silencing the barrel and QEV as at 500psi its gonna make one hell of a boom :twisted:

Posted: Thu Dec 11, 2008 4:49 pm
by POLAND_SPUD
well personally I wouldn't like to have 500 psi exhausting near my hand...

Posted: Thu Dec 11, 2008 5:09 pm
by VH_man
Just pipe the air from the QEV into the silencer on the Barrel! And the Exhaust from the valve.

Or make your own little silencer thingie for the two of them. I did this on MIKE, it works great.

Posted: Thu Dec 11, 2008 6:24 pm
by Ragnarok
POLAND_SPUD wrote:now why don't you put a bv that would allow you to cut chamber volume to silence the gun?
It would actually look pretty aesthetically poor. It would also cut ballistic performance. There are reasons why I've chosen the specific chamber dimensions in question, and changing that would harm performance.
POLAND_SPUD wrote:he is planining to use a slide valve for piloting (which can't be silenced) so he can't silence the gun anyway
ALIHISGREAT wrote:and then there is the QEV exhaust too....
I didn't say silence - I said suppress.
I have no pretences this is going to be a mouse-fart silencer. I just want less noise. Certainly no more than I'm currently generating with HEAL (unsuppressed), and ideally a whole heap less.

The air volumes from the QEV and slide valve are very minor, pittances to what's being dumped through the muzzle.
When I've done tests before with HEAL, if the muzzle blast is completely removed (i.e. if the main safety, which blocks valve from projectile, is left shut), the other mechanical noises of the launcher are insignificant.

Posted: Fri Dec 12, 2008 6:09 pm
by psycix
I have no pretences this is going to be a mouse-fart silencer. I just want less noise.
You mean:
I just dont want to blow my eardrums into my brain.



Side note:
When enduring a very loud explosion or shockwave, make sure you dont keep your mouth shut.
When you keep your mouth a lil bit open, the air can get into it and give backpressure behind your eardrums, so less damage will be done.

Posted: Fri Dec 12, 2008 6:36 pm
by Ragnarok
psycix wrote:You mean: I just dont want to blow my eardrums into my brain.
No, that's not what I mean. I have ear protection for that problem.

What I mean is: "I don't want a cannon that is too loud, as I believe I am already pushing the limits of what is reasonable to subject my neighbours to, and also because I don't want to alarm any passers by to the extent they choose to call the police."

Posted: Fri Dec 12, 2008 7:00 pm
by Ragnarok
EDIT: Crap. Mistaken double post. First one went through, I somehow ended up back on the submit screen again, saw it 30 minutes later and instinctively read it through, then hit submit - the fact that I had already posted it failed to register for some reason.

I plead only two and a half hours of sleep in the last 40 hours.

Posted: Sun Dec 14, 2008 6:44 am
by psycix
Ragnarok wrote:I believe I am already pushing the limits of what is reasonable to subject my neighbours to
One good blast without ear protection and they will never hear (and thus complain at) any noise again.
Though they will wonder where that annoying beep comes from. :roll: