Airgun noise descriptions - just an observation

[bobseagles]

At the risk of sounding too analytical or academic, for years I have heard the phrase used "mouse-fart" quiet, or other descriptions of PCP's noise that are hard to get a real understanding of loudness. 

If you shoot a .22 LR in a very wide open space (like a prairie), it will sound "quiet". If you shoot it in your basement, it will sound incredibly loud.

Perhaps the only way to get a valid measurement is to use a sound pressure meter measured from about 10 feet from the muzzle in a basement, or outside. Although all meters are not created equal, most (including the one you may have in your phone) are reasonably accurate compared to the phase "mouse-fart". AoA, Pyramydair and a few others use Extech sound meters, which provide a much more accurate measure of noise in dBs.

After reading hundreds reviews on various websites, you can't help but read one person have a completely opposite evaluation of the noise of another. You will read someone saying it is quiet as "mouse-fart", and another person saying the same PCP is not back yard friendly. I did not know mice flatulence was that loud !

How about an industry standard agreed to by the manufacturers and by custom producers, with the usual protection clause claiming they are not responsible for precision ?

MOD EDIT: Moved to General as this pertains to a wide variety of air rifles, not just PCP's

 

[John "spysir" Blount]

 Mainly do to history, ( and most folks seem to new to recall or care) I hate the "M-F" quite phrase. This phrase being coined by the 3rd ( that "I" know of) largest airgun thief in U.S. History.
Also quite can be nice but people did seem more careful when all most all made a good bit of noise. Every shot I have ever taken, airgun or otherwise, was legal when & where I was, I like it that way.
DB meters ( except $$$ ones) seem to vary largely.
Having owned several marauders, and being a bottom dollar rifle many have been exposed to "I" try to compare what my ears hear against the noise of a marauder - naturally they all vary a bit depending on fpe, ...-
In .22 a 30fpe HM1000 is much quieter than a .22 30fpe marauder.
Any of the AA rifles with the old style 16mm shroud ( which looked good also) are quitter than any of the newer 20mm shroded AA rifles at the same power level.

Quiet just doesn't matter to me ( I do own some quite rigs though) if it is legal to shoot I will pay attention to the relevant noise ordinance laws - we have none but other places I lived said things like no loud noise after 10:00pm- and shoot safely when ever I feel like it. Were it not legal I wouldn't shoot.

And whilst rambling , Video's seem to confuse folks the most, rightfully so. I simply can not believe how many people do not understand that most common video devices "clip" the sound GREATLY. Making most anything sound like a red-ryder. "In the video I saw it was SO quite" while that is the device automatically turning the sound down for a slit second to save the electronics or????? 

"Industry standard" LOL. No thank you.
Now an industry standard that claims anything about group size, at a given range with a given pellet YES!!! I only know of 2 manufactures that will stand behind their rifles regarding groups. ( that doesn't count crosman who try's but come on you cant expect sub-moa for under $400, but even they will send you a new barrel or rifle if groups are truly poor) .

One BIG question everyone seems not to ask is
exactly what is the policy on X rifle if it does not group well ( and it isn't the shooter). Anything over $1,000 "I" want to hear the answer to that one.


Now back to your normal sound level.


John

 

[azuaro]

"Now an industry standard that claims anything about group size, at a given range with a given pellet YES!!! I only know of 2 manufactures that will stand behind their rifles regarding groups." 
Feinwerkbau, Anschutz, Steyr, Walther give you the test card shot with the rifle at 50 Meters or 10 Meters when the gun is for ISSF competition, they also provide you with pellet brand, weight and velocity used for the test...In my 30+ years shooting and dealing with these guns I have never ever seen one of these guns that doesn't stand to their "Proof Targets" and in many cases I have seen guns that shoot much better than these targets...
I totally agree with you in that there should be an "Accuracy Industry Standard" as these companies have done it for many decades...


"Perhaps the only way to get a valid measurement is to use a sound pressure meter measured from about 10 feet from the muzzle in a basement, or outside..."
Better do it outside...In a basement there are echos and bouncing waves that would distort the actual noise produced by the gun...The problem with SPM's is that they measure the sound or noise that is present when the "Switch" is activated and the reading will not always be true...You have heard people saying that sound pressure meter XYZ is FASTER than meter ABC and this is what the "switch" in those meters does...The faster the switch the better the meter for what we are trying to measure (gun noise).

Consumer SPM's are OK for sustained noise (music, traffic, etc.) but no so much for measuring the noise that our guns make when we fire them...we would need to buy the "Good SPM's" that cost several thousand dollars...Nevertheless, we all use the "Cheap" meters and if we don't pretend to be too emphatic, these meters will provide us a fair estimation...

The db (decibel) scale is logarithmic based and not linear, and we have that for every 10 db the perceived noise doubles:
At 40 db we perceive noise at "x" level, at 50 db we perceive it as 2x, at 60 db the noise will quadruplicate (4x), at 70 db is becomes 8x and so forth...

We can always find (internet) noise levels of things that are a good comparison to start with...Noise levels like a whisper, a conversation, traffic on the streets, a train, jet engine, land mower, railroad, etc...

Regards,

AZ