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Posted: Sun Jun 03, 2007 4:53 am
by Marco321
Hey
I made a silencer for my pneumatic gun, i used lots of holes in the end of the barrel, 4 per set, and i used about 6 sets of holes, so i have about 24 holes for my silencer, i then stuffed cotton wool in there and put the outside of the silencer on. It does make a decent difference, but i was wondering if i needed to have baffles and if they would make a bigger difference, and if i used baffles would i have 1 large section cotton wool and the rest of the sections empty space like in a diagram i saw?.
Thanks
Marco
Posted: Sun Jun 03, 2007 6:59 pm
by VH_man
baffles make a HUUUGGEEEEE difference. nuf said. without them, your silencer is simply a shock dampener. with the baffles, your silencer is a real silencer and can actually lower the decible level of the sound, and not just change the frequency of the sound.
Posted: Sun Jun 03, 2007 7:24 pm
by Marco321
Oh thanks VH_man your a legend, im gonna put the baffles in
Posted: Sun Jun 03, 2007 8:58 pm
by chaos
also marco it would be more effective if you diddnt use a peice of the barrel inside the silencer if it was just your projectile passing through baffles it would be ideal.
Posted: Sun Jun 03, 2007 9:25 pm
by VH_man
yeah, also, a peice of barrel decreases accuracy a ton. any imperfection inside the supressor barrel makes your projectile spin wildly. theres a reason why real rifle silencers usualy give the bullet a 1mm clearance around the bullet. its so that the bullet doesnt hit the supressor and kill the accuracy. stick with baffles only, like chaos said.
Posted: Sun Jun 03, 2007 9:37 pm
by jackssmirkingrevenge
VH_man wrote:yeah, also, a peice of barrel decreases accuracy a ton. any imperfection inside the supressor barrel makes your projectile spin wildly. theres a reason why real rifle silencers usualy give the bullet a 1mm clearance around the bullet. its so that the bullet doesnt hit the supressor and kill the accuracy. stick with baffles only, like chaos said.
It depends what you're firing. It's ok if you're using relatively stable projectiles like BBs or marbles to use baffles only, but for most other ammunition then the "perforated barrel" method is the way to go to avoid catastrophic failure within the silencer.
For the same reason, firearm shotgun suppressors use the same construction:
It's also not necessarily going to have a negative impact on accuracy particularly if you make the silencer integral, after all it's how most integrally suppressed weapons like the
De Lisle carbine are made (and what marco did in this case), combining the perforated barrel with baffles, and the latter was good enough to be used as a close range sniper. the same is true of the Russian
VSS "vintorez".
Posted: Sun Jun 03, 2007 9:50 pm
by VH_man
the inner tube is not the exact same size as the actual barrel. it couldnt be, the bullet would slow down with the slowing gasses inside the supressor......
Posted: Sun Jun 03, 2007 9:57 pm
by jackssmirkingrevenge
VH_man wrote:the inner tube is not the exact same size as the actual barrel. it couldnt be, the bullet would slow down with the slowing gasses inside the supressor......
It is, indeed in most cases (like the de lisle and VSS quoted above) the inner tube actually *is* the barrel, because slowing down bullets is a great way of reducing the sound they make

for example the
HK MP5SD submachinegun is made for 9mm ammunition that is ordinarily supersonic in a normal barrel and it drops it so subsonic velocity.
The point here is that while as you suggested a perforated tube is going to have a negative effect on accuracy if on a removable silencer with a sloppy fit, on an integral silencer it has no effect whatsoever and indeed for most types of improvised ammunition used in spudguns it's the only way to go to avoid destroying your silencer with your first shot.
Posted: Mon Jun 04, 2007 1:43 am
by Marco321
OK cool, whats the best way to make or get baffles, i gave it a test with using glue from the hot glue gun, its alright, lowers the noise a little than without baffles. Any suggestions?
Posted: Mon Jun 04, 2007 1:49 am
by Pete Zaria
Marco321 wrote:OK cool, whats the best way to make or get baffles, i gave it a test with using glue from the hot glue gun, its alright, lowers the noise a little than without baffles. Any suggestions?
Depending on the size of your barrel you might be able to find metal washers of an appropriate size. Otherwise, I'd cut them from thin sheet metal. Sheet PVC would probably work fine, too.
Peace,
Pete Zaria.
Posted: Mon Jun 04, 2007 1:58 am
by chaos
Pete Zaria wrote:Marco321 wrote:OK cool, whats the best way to make or get baffles, i gave it a test with using glue from the hot glue gun, its alright, lowers the noise a little than without baffles. Any suggestions?
Depending on the size of your barrel you might be able to find metal washers of an appropriate size. Otherwise, I'd cut them from thin sheet metal. Sheet PVC would probably work fine, too.
Peace,
Pete Zaria.
ok then what about rubber, say 6mm thick. would that work? if i made a punch to cut the O-d then another for the Inner hole.
Posted: Mon Jun 04, 2007 2:05 am
by jackssmirkingrevenge
have you tried ply or balsa wood? balsa is readily available from hobby shops and very easy to work with, you can cut it with a craft knife and if you sandwich say two 3mm thick discs together with opposite grain you'll get a very strong and lightweight result, though the latter might not be an obvious advantage on a stainless steel launcher

Posted: Mon Jun 04, 2007 2:36 am
by Marco321
Ok, what about those cloth things you use to scrub dishes, would they work as baffles?
Posted: Mon Jun 04, 2007 2:55 am
by jackssmirkingrevenge
Ok, what about those cloth things you use to scrub dishes, would they work as baffles?
Not as baffles but rolled around the barrel in between the baffles and used as sound absorbing material, like here:

Posted: Mon Jun 04, 2007 2:56 am
by Marco321
Ok, so the baffles arn't in that picture?