LDCs for PCPs

[Nomadic Pirate]

After trying Neil's reflexed LDCs I will never again use any others.

[mrbulk]

I did this a while back ....

Thanks for the cool video, TJ!

[rkr]

There's the well known basic design that most manufacturers use and it gives good results. In addition vent holes can reduce or increase the noise level and the dB peak frequency can be tuned to give different types of sound - high pitch often sounds like less dB even if it's more. Other than that it's all about volume - based on my testing.

That’s basically my findings as well although I have not tried vent holes, its always seemed counterproductive to me.
Volume is king and if it’s a baffle design use the smallest aperture holes you can get away with without affecting accuracy or creating too much back pressure.

There's two ways to make those vent holes to work, either you slow down the air coming out of them to prevent the "bang" or you change the tone to be over 20KHz so you can't hear it.

Years ago in the old BSAOG (which is now in the bit heaven) a very well executed comparison of 12 different silencers was made using 12 fpe guns. I managed to find the data from that test from my HD (graph attached). Unfortunately I have no description saved but the test was done using one weapon in a silent location outdoors, 24 bit soundcard, good mic + audacity to crunch data. What can be learned:

1. Monocore units made for rimfire use (SAK) do not work well for airguns
2. The performance of traditional 3 chamber units is close to each other while HW remains on top
3. A modified unit (RancidTom's Hogan) easily outperforms off the self silencers

[mrbulk]

Some mysterious deliveries to the mrbulk household have grown the collection lately.

In order of length:

Huma 40 Std
valymurph ebay LDC
Rocker1
Sumo
Artemus CP2 factory unit
Geo ebay LDC
Tanto
MaxZ Bulk one-off custom miniature w/all aluminum monocore (no felt!)
ZeroDB

[Hangtown-Shooter]

Dang brother! Would you like the # for my new therapist? She specializes in AG addiction! 💩

 I was trying my best to keep it to myself until I received it, but I’m like an excited kid haha... and on top of that I’ve had a couple beers tonight while I give my pellet-smoker a good workout, and it’s almost like a form of truth serum lol... so Imma‘ let the cat out of the bag... I have a Neil Clague currently being custom made for my Cayden! 🤩

I hold this thread to blame btw 🤣

[Rallyshark]

Some mysterious deliveries to the mrbulk household have grown the collection lately.

In order of length:

Huma 40 Std
valymurph ebay LDC
Rocker1
Sumo
Artemus CP2 factory unit
Geo ebay LDC
Tanto
MaxZ Bulk one-off custom miniature w/all aluminum monocore (no felt!)
ZeroDB

You got a collection going there!  Let us know how the Huma works for you.  I'm curious on your thoughts, since we don't get a lot of people using them on here.  I'm also curious, because I haven't tried the shorter version you have.  Well, shorter than the one I have at least.   I've been using the "Standard+" MOD 40. 

Dang brother! Would you like the # for my new therapist? She specializes in AG addiction!

 I was trying my best to keep it to myself until I received it, but I’m like an excited kid haha... and on top of that I’ve had a couple beers tonight while I give my pellet-smoker a good workout, and it’s almost like a form of truth serum lol... so Imma‘ let the cat out of the bag... I have a Neil Clague currently being custom made for my Cayden!

I hold this thread to blame btw

I'm sure it will be sneaky quiet too!  He makes some good ones for sure.

[mrbulk]

Dang brother! Would you like the # for my new therapist? She specializes in AG addiction! 💩

  GOOOD one, Dave!

I was trying my best to keep it to myself until I received it, but I’m like an excited kid haha... and on top of that I’ve had a couple beers tonight while I give my pellet-smoker a good workout, and it’s almost like a form of truth serum lol... so Imma‘ let the cat out of the bag... I have a Neil Clague currently being custom made for my Cayden! 🤩

I hold this thread to blame btw 🤣

Uh-oh you did it now, cat's outta the bag and we MUST see pictures when you get her!

...gosh I love this forum...

[mrbulk]

Some mysterious deliveries to the mrbulk household have grown the collection lately.

In order of length:

Huma 40 Std
valymurph ebay LDC
Rocker1
Sumo
Artemus CP2 factory unit
Geo ebay LDC
Tanto
MaxZ Bulk one-off custom miniature w/all aluminum monocore (no felt!)
ZeroDB

You got a collection going there!  Let us know how the Huma works for you.  I'm curious on your thoughts, since we don't get a lot of people using them on here.  I'm also curious, because I haven't tried the shorter version you have.  Well, shorter than the one I have at least.   I've been using the "Standard+" MOD 40. 

Donny, so you "only" have the Standard+??? The Standard I received today is absolutely gargantuan compared to the (formerly) biggest one I have, the DonnyFL Sumo. So the Plus is what, a couple inches longer? That thing must be yuuuge! But man it must be silent. I tried to add one of those extensions to my order to make it five sections like your Plus, but they were sold out of the 40mm.

But it will be interesting to try it on the AR6K, the loudest gun I have at the time. The Sumo quieted it down somewhat, but it was still obviously a bit louder compared to the Akela and another PCP I have, with their factory spring loaded baffles already installed in the shrouds.

[rkr]

Huma Long 5/0 has the same volume and basic construction that's used in A&M Marksman. That one is the quitest silencer I have so Huma should work really well up to 150 fpe level. At 165 eur it is too expensive for me though, otherwise I'd get one and would test it against A&M which is only 80 euros.

[JungleShooter]

Question:
I'd be interested in an airgun silencer with a 2" (5cm) diameter.
Is there anybody else besides DonnyFl that makes them?

Matthias

[Long_Gun_Dallas]

Silent thunder ordnance makes some interesting designs.  I'd love to see some Independant comparisons with others and some new STO designs.

The Huma has pretty tight baffle clearance (6.5mm on 5.5mm  airgun)  the ability to strip air does have a noticeable a effect on noise reduction.  Most moderators leave more room for error, but the humas I've had were machined perfectly straight.  So, as long as your gun/mount is the same it will never be an issue.

I do have a very compact integrated mod on a pistol that is 6.2mm clearance on 5.5mm bore, and it is extremely effective for being very small in size and volume.  I'd does contain an air stripper and a tiny but functional shroud, so that helps too

[rkr]

Question:
I'd be interested in an airgun silencer with a 2" (5cm) diameter.
Is there anybody else besides DonnyFl that makes them?

Matthias

I have one for bigbore use. The problem is they start to show on your scope view.

[mrbulk]

I wonder when someone will make an offset unit, like the EdGun Leshiy.

[Rallyshark]

Donny, so you "only" have the Standard+??? The Standard I received today is absolutely gargantuan compared to the (formerly) biggest one I have, the DonnyFL Sumo. So the Plus is what, a couple inches longer? That thing must be yuuuge! But man it must be silent. I tried to add one of those extensions to my order to make it five sections like your Plus, but they were sold out of the 40mm.

But it will be interesting to try it on the AR6K, the loudest gun I have at the time. The Sumo quieted it down somewhat, but it was still obviously a bit louder compared to the Akela and another PCP I have, with their factory spring loaded baffles already installed in the shrouds.

Well, I originally got a Standard+, which is the same as yours, but with an extra 20mm section.  At the time, I was fighting some accuracy issues with a gun, and I stupidly drilled it out    Now it has the opening of about a .30 cal,lol.  I later added a 40mm section for a .25 to it.  In other words, a standard that isn't drilled out would probably work about as well as mine currently does.  It works amazingly well, considering the size of the hole on it and I'm using it on a .22 tuned to around 57 fpe.  It is actually still easily backyard friendly.  The odds of clipping are extremely low though,haha.  I'm just kicking myself for drilling it out...  I sure wish I could buy the end cap for them by itself.  I'll probably end up getting another Standard at some point. 

[mrbulk]

Donny, so you "only" have the Standard+??? The Standard I received today is absolutely gargantuan compared to the (formerly) biggest one I have, the DonnyFL Sumo. So the Plus is what, a couple inches longer? That thing must be yuuuge! But man it must be silent. I tried to add one of those extensions to my order to make it five sections like your Plus, but they were sold out of the 40mm.

But it will be interesting to try it on the AR6K, the loudest gun I have at the time. The Sumo quieted it down somewhat, but it was still obviously a bit louder compared to the Akela and another PCP I have, with their factory spring loaded baffles already installed in the shrouds.

Well, I originally got a Standard+, which is the same as yours, but with an extra 20mm section.  At the time, I was fighting some accuracy issues with a gun, and I stupidly drilled it out    Now it has the opening of about a .30 cal,lol.  I later added a 40mm section for a .25 to it.  In other words, a standard that isn't drilled out would probably work about as well as mine currently does.  It works amazingly well, considering the size of the hole on it and I'm using it on a .22 tuned to around 57 fpe.  It is actually still easily backyard friendly.  The odds of clipping are extremely low though,haha.  I'm just kicking myself for drilling it out...  I sure wish I could buy the end cap for them by itself.  I'll probably end up getting another Standard at some point.

Ahh, understood. I have heard it is wise anyway to have a slightly enlarged pathway through the LDC, apparently it does not detract significantly from the sound dampening ability. BUT - when I went to add a extension section, all they had were 30mm barrels, nothing in 40mm so I did not even get to explore the option of ordering something slightly larger, internal bore size anyway, dang it...

[Rallyshark]

I've always gone up one caliber on my LDCs, just to be safe.  That is especially a good idea for me, since I know who the dummy is that machined my barrels(me),lol!  I just went in and measured the Huma that I drilled out, and it is .386" or around 9.8mm.  So yeah, a little large for a .22    Like I said though, it is still plenty quiet.  I don't expect the difference in one that wasn't drilled out being that much, but it still annoys me that I did it.  That's what happens when you work on guns when you're in a hurry or getting frustrated....  The problem never was the LDC, it was barrel movement. 

Hurry up and test that thing Charlie!

[Mr.P]

 Just got a 3d printer up and running. Also a couple of 10" x 2" Chinese "fuel filter" tubes/caps/orings / filters sets, again only $16 a pop...

So I have been printing different baffles to try out in those tubes along with hair curlers and other home made stuff.

Getting some very good results but it's all just random messing around and having fun, not getting really systematic.

These would be great for anyone wanting a 2" can. 

Am I crossing a line here?  Is this general and vague enough? 

[mrbulk]

Hey Mister, we're just talking about fuel filters, aren't we? Hehe...

Donny I just need to figure out The Way to test. Indoors everything overwhelms my sound meter, and outdoors I gotta time it between nosy neighbor head poke-outs...especially when doing the no-LDC comparo shots...

[Rallyshark]

Hey Mister, we're just talking about fuel filters, aren't we? Hehe...

Donny I just need to figure out The Way to test. Indoors everything overwhelms my sound meter, and outdoors I gotta time it between nosy neighbor head poke-outs...especially when doing the no-LDC comparo shots...

I'm not looking for sound meter readings really.  I'm just looking for your thoughts on how well it seems to work on your guns is all.  Just your "seat of the pants" thoughts on it, if that makes sense.  I'm really curious to see how it compares to the Sumo, because I had a Sumo once and sold it.  It just didn't do what I hoped it would do, but the Huma blows it away from my memory.  That's isn't necessarily a knock on the Sumo, but it just didn't work well for me. 

[rkr]

I've always gone up one caliber on my LDCs, just to be safe.  That is especially a good idea for me, since I know who the dummy is that machined my barrels(me),lol!  I just went in and measured the Huma that I drilled out, and it is .386" or around 9.8mm.  So yeah, a little large for a .22    Like I said though, it is still plenty quiet.  I don't expect the difference in one that wasn't drilled out being that much, but it still annoys me that I did it.  That's what happens when you work on guns when you're in a hurry or getting frustrated....  The problem never was the LDC, it was barrel movement. 

Hurry up and test that thing Charlie!

That should make some nice low thump when fired. I actually use 9mm exit hole in one of my HWs for that reason. I've never gone for 9+mm baffle holes for small bores but for internal baffles there's really no measurable difference whether you go 1mm or 2mm oversize of the bore.