Finally! Got rid of ALL the "PING" Noises

Here is audio from my iPhone. The gun is indoors in a hallway, on the floor, supported by a bipod. Phone is on ground about 8 inches to right of cocking lever.

You may need to use earphones to get a good listen, but you should be able to pick up the complete lack of ringing. Also, this gives an idea what DonnyDu’s LDC achieves.

[audio src="http://www.bunnyandbear.net/talon/Vulcan%20Firing%20Cycle.m4a" /]

EDIT: Changed order of importance for noise reduction after more recent testing with gen 3+ spring and hammer configuration.

I was asked to outline how to eliminate all the ping noises including this last one.

Here they are in order of importance.

1. Firing Valve Spring and Retaining Disc
This is a medium pitched “twoong” that last about 1/4 second after firing. It is as loud as the main spring twang, but from within the rear of the air cylinder and thus difficult to locate its source until now.

Strking the firing valve makes the spring and its retaining disc ring with surprising loudness. This is easily demonstrated when the valve assembly is off the air cylinder. Just rap the firing valve pin with your fingernail and you will hear the spring and the spacer ring loudly.

Damp this with a simple, arrow shaped, damper pushed into the center hold of the retaining disc.
Once, more that old silicone iPod cover was used as the raw material. Cut to a shape as shown in this image. The shape holds it in place.

2. Hammer Spring Damper
This is the relatively low pitched “Pong” noise of the hammer spring. Of the three ping noises, sources this is the 2nd loudest. Newer Vulcans have a silastic tube on the spring to tame this noise. Here on the forum, a rubber grommet is often used. Personally, I use a foam earplug that has had a hole punched through it as my damper. It works very well.

To install, you must remove the hammer and hammer spring completely. Feed the hammer and spring through foam to install. Be sure to position the foam so it does not come into contact with the small cocking return spring.

While you are in that portion of the gun, you can also damp the vibrations of the small cocking return spring by pulling a bit of foam into the center of that spring. Look carefully inside that spring in this image and you can just make out the gray foam.

3. Regulator Air Chamber Spacer
This is the aluminum tube that creates the regulated air chamber between the firing valve assembly and regulator. Ringing from this is higher pitched “ting.” It is not as loud as the hammer spring “pong,” but very noticeable.

The classic approach is to lathe grooves for o-rings near each end of the spacer. O-rings then damp the spacer’s ringing. I don’t have a lathe, but instead put 1.5 layers of electrical tape around the spacer. The tape will need to be slit to make it narrow enough. Two layers will be too thick.

EDIT: Omit the silastic washer in my picture. It ends up entirely inside of the spacer tubing due to the high compression force between the spacer and regulator. It isn’t needed with the 1.5 layers of electrical tape in place.

What doesn’t work…..
“Air Tube De-Pinger”
Your read about these on the internet. People stuff rolled up tubing, fancy baffles, or a bottle brush into their air cylinder to break up the traveling wave. That does nothing on a Vulcan. The shock wave from the firing valve is blocked by the regulator. No noise producing wave bounced back at for in the air cylinder. I tried a bottle brush. Had zero effect. Don’t add such a “de-pinger” to a Vulcan. It just reduces your air cylinder usable volume.

Now that I have all three major ping noises tamed (and my bottle brush “de-pinger” removed), my Vulcan is finally free of the pinging that annoys with each shot.

Now all I hear is the hammer slap and puff of air. Ringing free bliss at last. :biggrinn: :biggrinn: :biggrinn: