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Machineguntony · May 7, 2014, 10:57 PM

http://www.silencerresearch.com/sile...efinitions.htm

I am not an expert on silencers, but I do like to learn about things. Here is what I know from my research.

An ablative is a cooling medium, such as water, oil, or anything that can cool a silencer.

The sound of muzzle blast is kinetic energy expressed as sound waves. The way a silencer works is that the silencer takes some of the kinetic energy and turns the kinetic energy into heat energy, thereby reducing muzzle blast.

An ablative, such as water, works by allowing the silencer to have a higher heat absorption threshold, thereby allowing the silencer to convert more kinetic energy into heat energy. With more kinetic energy turned into heat energy, there is less kinetic energy to expand the air around the muzzle of the gun/silencer. With less kinetic energy to expand the air, there is a smaller 'pocket' of collapsing air that creates the thunderclap that we know as 'muzzleblast'. This results in a quieter gunshot sound.

My goal of experimenting with an ablative medium was to find something that will hold the maximum amount of heat possible, given equal volume.

I have really been enjoying my new toys and I have experimenting with my favorite ablative medium.

So far, my favorite is hand sanitizer. Hand sanitizer is less messy than water, and seems to last longer; about five shots until it loses all sound reduction ability. Hand sanitizer is also neutral on the grip. An ablative, like motor oil, gets the gun really slippery, and a slippery gun is pretty dangerous, especially if the gun is a machine gun.

Hair gel, I do not like, as the hair gel does the opposite of oil: it makes the gun unbearably sticky.

Water is free as an ablative but it has the downside of being really messy. When I say messy, I mean that there is ejection of water, mixed with gunpowder, out the back of the ejection port. This happens whether it is a pistol or rifle. A thicker ablative does't splatter as badly because it is thicker. Water just flies all over the place. By the time I was done shooting about 200 rounds, I had black freckles all over my face and arms.

So after doing some reading about how ablatives work, I came up with an idea. I used canola oil because it has a really high smoking point. The canola oil didn't work any better than regular oil. Upon further research, my guess is that a higher smoke point does not equate to a higher heat retention ability.

So my next experiment was to try ice cold water. The ice cold water was the best ablative. It lasted the most shots before losing effectivenes (about 10 shots). It also had the greatest sound reduction.

Ice water, while an awesome ablative, is a pain to carry around and maintain its temperature prior to use, obviously. So it has significant downsides.

Btw, I would measure my sound reduction via an app. I can not vouch for the accuracy of these apps, but they're available in the Apple store, if anyone wants to try.

On a side note, shooting the ice cold water ablative brought a rather interesting observation. I shot the ice cold water in a subsonic 45 and a supersonic 9mm load. I never understood what people meant when they were talking about 'subsonic' ammo, but the sonic boom created by the bullet's flight is actually nearly as loud as the muzzle blast itself, maybe 50% of the noise component (a guess). The suppressed subsonic 45 was significantly quieter than a suppressed supersonic 9mm. I could hear the sonic boom of the 9mm.

Also, with the .45, the loudest sound was the thud of the bullet hitting the backstop.

Very interesting stuff.

I am not saying any of the above is correct. I am learning as I go, so if anyone can correct me or provide clarifyng info, I would really appreciate it.

May 7, 2014, 10:57 PM	#4
Machineguntony Senior Member Join Date: June 22, 2013 Posts: 1,277	http://www.silencerresearch.com/sile...efinitions.htm I am not an expert on silencers, but I do like to learn about things. Here is what I know from my research. An ablative is a cooling medium, such as water, oil, or anything that can cool a silencer. The sound of muzzle blast is kinetic energy expressed as sound waves. The way a silencer works is that the silencer takes some of the kinetic energy and turns the kinetic energy into heat energy, thereby reducing muzzle blast. An ablative, such as water, works by allowing the silencer to have a higher heat absorption threshold, thereby allowing the silencer to convert more kinetic energy into heat energy. With more kinetic energy turned into heat energy, there is less kinetic energy to expand the air around the muzzle of the gun/silencer. With less kinetic energy to expand the air, there is a smaller 'pocket' of collapsing air that creates the thunderclap that we know as 'muzzleblast'. This results in a quieter gunshot sound. My goal of experimenting with an ablative medium was to find something that will hold the maximum amount of heat possible, given equal volume. I have really been enjoying my new toys and I have experimenting with my favorite ablative medium. So far, my favorite is hand sanitizer. Hand sanitizer is less messy than water, and seems to last longer; about five shots until it loses all sound reduction ability. Hand sanitizer is also neutral on the grip. An ablative, like motor oil, gets the gun really slippery, and a slippery gun is pretty dangerous, especially if the gun is a machine gun. Hair gel, I do not like, as the hair gel does the opposite of oil: it makes the gun unbearably sticky. Water is free as an ablative but it has the downside of being really messy. When I say messy, I mean that there is ejection of water, mixed with gunpowder, out the back of the ejection port. This happens whether it is a pistol or rifle. A thicker ablative does't splatter as badly because it is thicker. Water just flies all over the place. By the time I was done shooting about 200 rounds, I had black freckles all over my face and arms. So after doing some reading about how ablatives work, I came up with an idea. I used canola oil because it has a really high smoking point. The canola oil didn't work any better than regular oil. Upon further research, my guess is that a higher smoke point does not equate to a higher heat retention ability. So my next experiment was to try ice cold water. The ice cold water was the best ablative. It lasted the most shots before losing effectivenes (about 10 shots). It also had the greatest sound reduction. Ice water, while an awesome ablative, is a pain to carry around and maintain its temperature prior to use, obviously. So it has significant downsides. Btw, I would measure my sound reduction via an app. I can not vouch for the accuracy of these apps, but they're available in the Apple store, if anyone wants to try. On a side note, shooting the ice cold water ablative brought a rather interesting observation. I shot the ice cold water in a subsonic 45 and a supersonic 9mm load. I never understood what people meant when they were talking about 'subsonic' ammo, but the sonic boom created by the bullet's flight is actually nearly as loud as the muzzle blast itself, maybe 50% of the noise component (a guess). The suppressed subsonic 45 was significantly quieter than a suppressed supersonic 9mm. I could hear the sonic boom of the 9mm. Also, with the .45, the loudest sound was the thud of the bullet hitting the backstop. Very interesting stuff. I am not saying any of the above is correct. I am learning as I go, so if anyone can correct me or provide clarifyng info, I would really appreciate it. __________________ Sent from Motorola DynaTac 8000x Last edited by Machineguntony; May 7, 2014 at 11:14 PM.