Clarification of Dry Fire #'s

[TandKHunting]

Anybody with access to the equipment could drop the firing pin on a spent case and see what the reading is. That might tell us if the 120 is the firing pin or something else. @TandKHunting it’s for science!

I stopped wasting my time arguing anything on here. I also don't have time for tests that prove nothing. lol

 

[Formidilosus]

Yeah that's a waste of time it's nowhere near 120dB.

Are you positive? I don’t actually know- but it absolutely meters at 120 dB plus.

Not sure if it's because of doing a million dryfires, but I never made that connection that hearing the firing pin drop would also mean it was at 120 dB. There must be something in the nature of the duration of the sound that's keeping it from causing ear-ringing after hundreds of reps.

I don’t think our perception of sound levels is all that great.

Any idea what dBs the actions of a cycling AR or pistol with subs comes in at?

An AR closing on an empty magwell is mid to high 120’s- to low 130’s at SE.

I can't imagine that anyone could have meant that the firing pin striking a primer (insulated by like a half inch of steel) is actually generating 120dB impulses. That's like hammer on anvil level noise.

Maybe. It absolutely meters +/- 120 dB (A).

I'm wondering if what Form is saying is that when the muzzle blast (with a can) is measured at 120 dB, you can also discern the action noise. That doesn't mean that the action noise is 120 dB by itself. ​

Again- the meters could all be BS. But dry fire absolutely meters +/- 120 DbA.

I stopped wasting my time arguing anything on here. I also don't have time for tests that prove nothing. lol

You don’t believe it is instructive for the consumer to know enough to recognize absolute BS numbers that are not possible, when companies state them?

 

[Billy Goat]

You don’t believe it is instructive for the consumer to know enough to recognize absolute BS numbers that are not possible, when companies state them?

I feel like this is the hang up.

For everything that I have seen/read on db numbers, 120 seems obviously loud. Like when I'm using a chainsaw, people hundreds of yards away know. Dry firing a firearm, the noise isn't heard that far away.

And certainly don't sound the same when you are standing next to someone doing either as well.

So just trying to wrap my head around how they are so similar.

 

[Formidilosus]

Could the meters be absolute BS- sure. But that also means any numbers that are in the same realm for supersonic rounds- are also complete BS.

 

[Formidilosus]

I feel like this is the hang up.

For everything that I have seen/read on db numbers, 120 seems obviously loud. Like when I'm using a chainsaw, people hundreds of yards away know. Dry firing a firearm, the noise isn't heard that far away.

And certainly don't sound the same when you are standing next to someone doing either as well.

So just trying to wrap my head around how they are so similar.

I don’t know. The only thing I do know, is that companies claiming super sonic cans to be in the mid to low 120’s needs to be viewed with extreme skepticism. Extreme.

 

[Billy Goat]

Could the meters be absolute BS- sure. But that also means any numbers that are in the same realm for supersonic rounds- are also complete BS.

Maybe I'm not understanding how they are working, but couldn't it be possible they are metering similar because of the differences in distances?

You have a microphone that is only a few inches off the sound in that video, comparing to feet away.

I can't view what the meter is actually reading, but I assume that's the premise of the video.

 

[Billy Goat]

This might be incorrect, its from the Google.

"Sound level drops by roughly 6 dB every time you double your distance from a sound source. For example, if sound is 100 dB at 1 meter, it will be approximately 94 dB at 2 meters, and 88 dB at 4 meters."


Using that, if microphone is 6" off one source, and 24" from the other source, the db rating will be 12 decibels higher on the object at 6" than 24" away.

Or I'm mathing wrong.

 

[alexnelon]

I don’t know. The only thing I do know, is that companies claiming super sonic cans to be in the mid to low 120’s needs to be viewed with extreme skepticism. Extreme.

This point is indisputable.

I've said before and I'll reiterate, sound metering is witchcraft and it's easy to get readings that are completely wrong and have no explanation why.

I don't think sound meters are having a positive effect on the suppressor industry and they're causing more confusion than anything.

 

[TandKHunting]

I don’t know. The only thing I do know, is that companies claiming super sonic cans to be in the mid to low 120’s needs to be viewed with extreme skepticism. Extreme.

Our stuff is at PEW Science. Will see how good it is. I will be sure to post the numbers on here specifically for you form. You can see how our can actually performs. Not just dB, but impulse, FRP, gas management, etc.

I literally showed you the video of the meter reading. I wasn't lying or being deceitful. That's literally what the meter was reading out at 6 inches right of the shooter's ear. Do I think the meter was off that day now? Absolutely. I'm a man. I can admit when I'm wrong. We did change mic orientation and have a new video up that more accurately portrays numbers while we wait for PEW Science. Once that drops...the discussion ends. I don't need to meter another thing and won't unless it's for internal testing. I will just send every can to PEW Science and post the numbers on here. That's what every company needs to do because average dB doesn't mean anything if a can has bad FRP, bad impulse, and inconsistent gas management.

That's why a suppressor with good average muzzle and ear numbers can be ranked #10 or #13 on PEW Science. Because that's only one portion of suppressor performance that will tell you if a can is bad, average, good, or elite.

I will say, your numbers are not accurate either. You have a meter that captures peak at 48 mHz. Far too slow to capture accurate peak numbers.

If you can drop the coin for an impulse system...maybe I and others here will start listening to you more. Until then...

 

[alexnelon]

This might be incorrect, its from the Google.

"Sound level drops by roughly 6 dB every time you double your distance from a sound source. For example, if sound is 100 dB at 1 meter, it will be approximately 94 dB at 2 meters, and 88 dB at 4 meters."


Using that, if microphone is 6" off one source, and 24" from the other source, the db rating will be 12 decibels higher on the object at 6" than 24" away.

Or I'm mathing wrong.

Sound metering is a science and it's not something you can learn how to do correctly from reading the manual for a device.

The kicker is even if done correctly, the numbers don't really matter in practice anyway.

It quite literally is a waste of everyone's time to argue about it.

 

[TandKHunting]

Sound metering is a science and it's not something you can learn how to do correctly from reading the manual for a device.

The kicker is even if done correctly, the numbers don't really matter in practice anyway.

It quite literally is a waste of everyone's time to argue about it.

The more I have dived into suppressor testing and analyzing data, the more I see that dB at muzzle and ear is important, but those are only two data points. There is a list of data points just as important, but can only be obtained from impulse meters and other highly expensive audio capturing equipment.

I know from previous posts you have some experience in this field.

That's why PEW Science is literally the best standard right now. It analyzes the entire suppressor performance. Not just one or two data points.

 

[Formidilosus]

Maybe I'm not understanding how they are working, but couldn't it be possible they are metering similar because of the differences in distances?

You have a microphone that is only a few inches off the sound in that video, comparing to feet away.

Shooters ear measurements are from where the microphone is in the video.

I can't view what the meter is actually reading, but I assume that's the premise of the video.

The dry fire metered between 125-128. The premise is that really low dB readings from companies with super sonic rounds is BS.

 

[Billy Goat]

Shooters ear measurements are from exactly where the microphone is in the video.

Right, so trying to standardize the distance off the barrel for the most part. But comparing sound numbers from 6" away(the action) and the end of the barrel/muzzle device 24" away is an example of what I was saying. 120db at 6" would be 132db at 24"

 

[alexnelon]

The more I have dived into suppressor testing and analyzing data, the more I see that dB at muzzle and ear is important, but those are only two data points. There is a list of data points just as important, but can only be obtained from impulse meters and other highly expensive audio capturing equipment.

I know from previous posts you have some experience in this field.

That's why PEW Science is literally the best standard right now. It analyzes the entire suppressor performance. Not just one or two data points.

When I say it doesn't matter, I mean that a bullet moving at supersonic speed is loud enough to damage your hearing so you should be wearing plugs or muffs anyway, and when you're wearing plugs with 24-28db NRR, the difference between 129db and 136db doesn't change anything on a macro level.

 

[TandKHunting]

When I say it doesn't matter, I mean that a bullet moving at supersonic speed is loud enough to damage your hearing so you should be wearing plugs or muffs anyway, and when you're wearing plugs with 24-28db NRR, the difference between 129db and 136db doesn't change anything on a macro level.

Totally fair stance for an end user with that simple observation, but from an engineering perspective the difference between the two matters a lot.

We are still trying to provide the absolute best performing cans on the market with tone, impulse, reduced FRP, manageable gas, etc. Whether hearing pro is used or not...it still matters.

A Honda Civic could get me from A to B, but I would rather have an F-150 because I'm a big guy, need room, and want to be comfortable. No different than a suppressor. Even with hearing protection, I have shot 5.56 cans that are not comfortable to shoot with because of gas smacking me in the face, or inconsistent performance. I have also stood 25 yards from someone shooting suppressors that were sharper and more fatiguing to me.

Hearing pro being worn regardless with what 5.56 can is being used doesn't mean I'm picking one with worse blow back, worse gas management, more FRP, and a tone that hurts everyone's ears near me. I'm still going to pick the best engineered suppressor I can.

 

[nm.otter]

A 120dB-ish suppressed rifle round has a very different sonic signature than that of a firing pin click.

The human ear is entirely capable of discriminating this sort of thing.

 

[Formidilosus]

Right, so trying to standardize the distance off the barrel for the most part. But comparing sound numbers from 6" away(the action) and the end of the barrel/muzzle device 24" away is an example of what I was saying. 120db at 6" would be 132db at 24"

Ok.

The entire point that I have stated from the beginning with all of this over a year ago is that- “too good to be true numbers, are too good to be true”. That’s it.

Super sonic rounds do not meter low 120’s in reality.

 

[Billy Goat]

The entire point that I have stated from the beginning with all of this over a year ago is that- “too good to be true numbers, are too good to be true”. That’s it.

So, you are trying to do the same thing by using a wildly wrong number?


It's in several posts around the forum that a dry fire is in the 120 range. I'm just trying to figure out where it's all coming from.



Are you believing that 120 is actually correct?

 

[TandKHunting]

So, you are trying to do the same thing by using a wildly wrong number?


It's in several posts around the forum that a dry fire is in the 120 range. I'm just trying to figure out where it's all coming from.



Are you believing that 120 is actually correct?

uh oh....

Form can't gaslight his way out of this one....

Let's see if he breaks down and says he is wrong. Because we all know he is.

 

[Formidilosus]

So, you are trying to do the same thing by using a wildly wrong number?

I am confused by what you are meaning/asking.

It's in several posts around the forum that a dry fire is in the 120 range. I'm just trying to figure out where it's all coming from.



Are you believing that 120 is actually correct?

For at least the third time- I do not know if 120 is correct for dry fire. I can’t say it any more ways than- the meters everyone is using, and people/companies are claiming to show super sonic rounds being low 120’s- also show dry fire as low 120’s.