LdC discussion , volume vs report reduction

LdC discussion , volume vs report reduction

Joined: April 28th, 2010, 12:23 am

November 24th, 2011, 3:32 am #1

Randy said its ok with him to discuss iirc.
First , how the hell does Neil clague make his so effective using almost no volume relative to other designs??In relation to airguns , heat isnt a factor so Id imagine baffle direction and shape (k,m ,a ) would have way different effects.Stuffing or packing ldcs seems to have the greatest result from my experience, dremel buffing pads being most effective,and ive seen scotchbrite nicely executed.
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Joined: November 17th, 2006, 3:51 am

November 24th, 2011, 2:26 pm #2


Have never had one of his apart to see. 

Have bought some from other makers, which worked well, and learned a bit about their construction...enought to make most of the shrouds/LDCs that I'm using.

Finding that my LDCs get smaller and smaller over time. Strong, but thin material can give good volume without a large external size.  Packing material does a better job in large volume/large sized LDCs, it actually seems to hurt small LDCs (guess the merial takes up the needed volume). The closer you can fit the baffle ports/holes (which is a matter of alignment), the less volume seems to be needed.

I've never figured out the ratio of volume to air use, other than more air use needs more volume,  Do know that a well made small LDC can be quieter than a large LDC
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Joined: April 28th, 2010, 12:23 am

November 24th, 2011, 2:48 pm #3

thats really true , the best packed one ive shot is on a cz400 and has a bigger diameter, maybe 1.5 and 8 inches long, so it has the displacement to donate to packing.
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Joined: November 17th, 2006, 3:51 am

November 24th, 2011, 3:23 pm #4


Kind of an evolution....although for looks #2 is prebably neater.

#1. A bit large,and seemed to have more volume than needed...a hollow type sound.  Packing might have helped.

[/IMG]

#2. Half shroud.  Nicer looking, but really no more effective. Hollow sound gone, but I missed the detachable nature of the LDC.

[/IMG]

#3. A more technical design, much thinner and lighter, and works just as well.  Low volume, but a more complicated path for the air, so suspect that air exits at the same velocity/energy as the larger units.

[/IMG]

Thinking that reather than containment, look to using up the air's energy in a zing-zag path May be wrong, but its working. 
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Joined: April 28th, 2010, 12:23 am

November 24th, 2011, 3:35 pm #5

ive been using air strippers as the first step in the last 2 i build , made these 2 for a friend so havent tested except on my 953 which happens to have the right size barrel.he has a 25fpe disco so that will be the true test.So far by bigger design of the 2 is still quieter regardless of the smaller having the more complex design
small one has
airstripper, washer, felt packing , washer, felt, washer , cap.very short like 5 inch overall at .75 o.d
big one has
airstripper, felt, long spacer, 3 washers, spacer washer , spring , permanent mrod shroud cap. simple design really , 8 inches long, more effective than first
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Joined: February 21st, 2009, 1:05 pm

November 24th, 2011, 6:43 pm #6

UK test's Neoprene wrap on curller's better than Felt And Shrink wrap on out side of LDC takes Metallic sound out.....Franky
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Joined: April 12th, 2002, 5:26 am

November 24th, 2011, 7:18 pm #7

Randy said its ok with him to discuss iirc.
First , how the hell does Neil clague make his so effective using almost no volume relative to other designs??In relation to airguns , heat isnt a factor so Id imagine baffle direction and shape (k,m ,a ) would have way different effects.Stuffing or packing ldcs seems to have the greatest result from my experience, dremel buffing pads being most effective,and ive seen scotchbrite nicely executed.
works as a series of air strippers, with a profile very similar to washers in production ldc's from the UK.

I'm working on a tensioned barrel with slits behind the choke, venting into the barrel shroud. If I can get good accuracy, it may be the ultimate invisible ldc.
Last edited by classicalgas on November 24th, 2011, 7:18 pm, edited 1 time in total.
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Joined: April 28th, 2010, 12:23 am

November 24th, 2011, 7:28 pm #8

to the mrod design?? washers and alternating orings has been somewhat effective , id tried diffeent spacing between each baffle and that seems to make a difference depending on the gun, larger spacing seems to work with c02, with pcps the smaller spacing like the tko breaks seems to work better.
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Joined: May 15th, 2009, 6:48 pm

November 24th, 2011, 8:36 pm #9

works as a series of air strippers, with a profile very similar to washers in production ldc's from the UK.

I'm working on a tensioned barrel with slits behind the choke, venting into the barrel shroud. If I can get good accuracy, it may be the ultimate invisible ldc.
There was a centerfire gunsmith doing that several years ago, both ported and unported barrels. I believe he EDM-ed his ports, and reported fantastic results. ATF shut him down because of the "sound attenuation", but that's not an issue for airrifles. I've considered having a Volquartsen .22lr barrel ported, but I can't find anyone to do it cheaply, and then there are the legal issues....
Jeff
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Joined: March 1st, 2002, 12:22 am

November 24th, 2011, 9:54 pm #10

Kind of an evolution....although for looks #2 is prebably neater.

#1. A bit large,and seemed to have more volume than needed...a hollow type sound.  Packing might have helped.

[/IMG]

#2. Half shroud.  Nicer looking, but really no more effective. Hollow sound gone, but I missed the detachable nature of the LDC.

[/IMG]

#3. A more technical design, much thinner and lighter, and works just as well.  Low volume, but a more complicated path for the air, so suspect that air exits at the same velocity/energy as the larger units.

[/IMG]

Thinking that reather than containment, look to using up the air's energy in a zing-zag path May be wrong, but its working. 
redirection and containent are key. So yea, making the air follow a zig zag path is good

 


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