Thread: Suppressor effectiveness - Think about this!

Originally Posted by 6x47

Looks like I wasted time typing (post #59)

Here, borrow some of my wall.

All my rifles have a suppressor because it makes it so much quieter and generally more pleasant to shoot as @timattalon says so very well here. http://www.nzhuntingandshooting.co.n...tml#post457898

First time i went hunting with the suppressed 243 wearing earmuffs off the back of a ute after wallabies I thought I'd had a failure to fire and started pulling everything apart.

Originally Posted by 6x47

Looks like I wasted time typing (post #59)

Nah only post #104

It clearly was for you.
I won't bother pointing out two things in your post where you're barking up the wrong tree.

And you've got a high-grade impulse SLM just laying about? Model?

With regards to the original post and what suppressors do and dont do.

The effects of suppressors on the environmental noise have been researched quite a lot here in Finland.

If a firearm and its noise is being observed from the front sector, a suppressor will have neglible effect as the major noise source is bullet flight noise ( c. 150 dB 1m from the bullet path on a .308 Win for example )

However, there is a greater effect to the side and rear of the shooter.

Take these levels for example from a test done by Dr. Rauno Pääkkönen back in 2003 ( a promiment expert in this field in Finland )

Noise suppression to a level of 65 dB

Calibre w/o a suppressor w/suppressor

.308 5000 m 300 m
.222 4000 m 200 m
.22 200 m 50 m


Best Regards!

Tuukka Jokinen
Ase Utra sound suppressors

Thank you Tuukka for this information.

Scandinavians have lead the world on the noise damage issue, firstly in chainsaws then more recently in firearms.

Originally Posted by 6x47

Have you seen that extensive NATO publication "Damage Risk from Impulse Noise"? If not, I can email it to you

If this isn't it http://natorto.cbw.pl/uploads/2000/9/EN-011-$$ALL.PDF then yes, please email it.


Thanks for that info Tuukka. I have looked all over and can't find the article. Can you provide a link to the whole thing?

No, that's the one ODL.
I've searched but can't find any evidence Johnson's proposed modelling has ever progressed to an ANSI std.

Tuukka's posts raises just as many questions as it answers IMO.

The tests we were involved in were conducted "to the side of the firing point" and only registered 52 dB from an unsupresssed 7.62x51 at 450 metres.

The supposed noise from "bullet flight path" of 150 dB must be quite close to the muzzle or otherwise those people who mark targets would be as deaf as posts I'd think - and I've done enough of it, in the old days hardly anyone wore ear protection doing it, even now heaps of people don't bother and its certainly not mandated on range operating procedures.

Originally Posted by ODL

If this isn't it http://natorto.cbw.pl/uploads/2000/9/EN-011-$$ALL.PDF then yes, please email it.


Thanks for that info Tuukka. I have looked all over and can't find the article. Can you provide a link to the whole thing?

Hi,

It was a Finnish language article, of which I made my own english translation, primarily to give to any of our distributors who were interested in it.

Regards!

Tuukka

Originally Posted by Tentman

Tuukka's posts raises just as many questions as it answers IMO.

The tests we were involved in were conducted "to the side of the firing point" and only registered 52 dB from an unsupresssed 7.62x51 at 450 metres.

The supposed noise from "bullet flight path" of 150 dB must be quite close to the muzzle or otherwise those people who mark targets would be as deaf as posts I'd think - and I've done enough of it, in the old days hardly anyone wore ear protection doing it, even now heaps of people don't bother and its certainly not mandated on range operating procedures.

Hi, can you specify the equipment that was used in your tests?

As for the 150 dB, as I wrote above that is the peak level from a distance of 1 m from the bullet flight path for a .308 Win.

Regards!

Tuukka

Originally Posted by Tentman

The supposed noise from "bullet flight path" of 150 dB must be quite close to the muzzle or otherwise those people who mark targets would be as deaf as posts I'd think - and I've done enough of it, in the old days hardly anyone wore ear protection doing it, even now heaps of people don't bother and its certainly not mandated on range operating procedures.

No, the bullet flight noise is usually taken 90 degrees off the axis of the bullet path and one meter to the side. It is irrelevant how close the actual gun is (past 100 meters anyway). The only factor is the size of the bullet and that it is still supersonic. The numbers indicated are consistent with tests done by Dater in the states of 152 for 308 and 147 for 223. I have not recreated these tests because the current body of knowledge is pretty well defined.

Doubling the distance will roughly drop 6db. So when patching in the butts you will be around 2m from the bullet flight causing a reduction. I usually wear spongies when patching.

Tuukka, can you link the original article in Finnish? Usually tech articles are decipherable even if I am illiterate in the language.

What would be the noise of a 50 cal bullet shot from a 50 bmg if you were testing at 1 m from its flight path?

I haven't seen any data on the 50 so if you want to bring one up to Rotorua some time, we could run the test and find out. While we are there we could run the others jsut for reference too.

I wish I could own one, but unfortunately you will have to find somebody else for the 50:-(