Not really a fit for NFA forum as this is actually more of a question of ear safety.
I keep reading that suppressors do not make supersonic ammo ear safe.
My question is if the suppressor is advertised for a 31dB NRR (Dead Air Sandman-L) and ear plugs have a NRR of 22-32, how can the suppressor not be ear safe?
Is it the supersonic crack of the bullet that prevents the safe hearing level?
Is this just a general assumption a can will not make the report ear safe due to the smaller cans not reducing the noise as well as the behemoth Sandman-L?
Mostly the supersonic crack. However, there’s also the issue that the volume at the muzzle can be more than 50-60db above the hearing safe threshold, depending on the cartridge and barrel length. I don’t think this is common, but it could happen with a large bore, high pressure cartridge in a short barrel.
YES. The best way to experience this is in the target pits for a 600 yard competition. You will not hear the report from the muzzle, but the crack of each bullet passing above will be almost as loud. For the big ones it may seem louder! And this is when they are down to 1500-1800fps. The supersonic crack is louder still at higher velocity.
Wasn’t sure where they take the sound reading from.
Wish I had a range with 600yds within even an hour drive from me.
Ok, guess I knew the answer. I was just hoping that the suppressor was more benificail for the shooter than those around the shooter. I know, I know, it all depends on the needs of the shooter.
I love my Sandman. The neighbors get agitated with more than 22fire, so the sandman allows me to cheat some on that front. It’s a shame when 25 acres gets too small!
I think the SPL readings are taken from the position of the shooter’s ear, but I’m not sure if that’s consistent.
Both shooter and bystanders benefit greatly from any suppressor.
The experience of shooting at 600 yards or longer is worthwhile, find a way to do it even if it means an overnight trip. It’s much different from, and to me more interesting than, shooting at 100 yards and less.
Buddy of mine has a hunting lease about 4 hours away. I went out there to shoot my Barrett a few years ago. We got out to 660yds. Had all the elevation I could get out of my VX-III to get it doped.
It was turkey season and the club would not let us take vehicles or 4wheelers off the road to check impacts. So it was about a 1500yd treck one way to check the target because of the hills of the pipe line. The target was on hill 3.
Here we are lighting off XM33 and we can’t drive a 4wheeler to check the target!
I was shooting at a letter sized piece of white paper. I nicked it on the right, nicked it on the top, and pulled it just left once I had the scope dialed in.
Never realized how much has to come together to make those long shots. Breathing, shooting between heartbeats, shooting before eye strain sets in, oh yeah, and the calming back down after the 3000yd walk!!
That is absolutely the case in my experience. Almost all the suppressed rifles we shoot are (at best guess) hearing safe for the shooter. If I’m out front of any rifle the crack seems to be too loud to be hearing safe.
The other factor is (on auto loading guns) port “snap”. I had one are I had to quit shooting suppressed because, for whatever reasons, the port snap was so loud, it hurt my right ear when firing it.
I still use hearing protection when shooting suppressed. It’s still loud even with a can on the end. Some are louder than others and I will agree that it is bearable without but for me I don’t want any more hearing damage later in life than I already have from working in a power plant…
Yeah, my dad did me no favors taking me out shooting as a kid. 357 magnum, 44magnum, single six (don’t laugh, they are loud!) all without protection. He broke out the muffs and plugs later in life, but the damage was already done. I can remember not being able to hear until mid afternoon the following day.
My kids have never been exposed to an unsuppressed round. They shoot the standard velocity CCI suppressed, so we go muff free for that. Anything more and it is suppressed and muffs (for them and me).
109db is not necessarily good to go, at that level you can begin to suffer hearing loss with less than two minutes exposure. Depends on your dosage each time in order to forsee cumulative results.
I don’t shoot anything, suppressed or unsuppressed, without double protection - plugs and muffs.
To get to the crux of the matter it’s difficult to shoot AR’s with full-blown muffs because they can interfere with your cheek weld (yes, I’ve tried many).
So the solution would seem to be: ear plugs AND the Otis Ear Shield.
(And I’m assuming no suppressor use since a lot of people don’t have that option).
AND…to muddy the waters: is it possible to sustain hearing damage without “perceived” loudness, i.e., if you can note that the sound is no longer uncomfortable or ear-splitting with protection–is that NOT a reliable indicator of how effective the ear protection is?
dB safe levels have more to it than just a peak dB. There is a duration of time and cycle per second. So a single pulse of 109 might be the equivalent to 90 constant. I have a good friend that has a brother that is an Otolaryngologist. I will see if he can give some insight on this.
I double up at all times. Ear plugs then electronic muffs turned all the way up. The amplified muffs make it so I can hear an instructor even with good quality ear plugs in.
With a reduction of 20-25db, most suppressors are not hearing safe enough for me. I’d still be wearing plugs or headphones at the range.
Another thing: raw dB numbers may not tell the tale if the majority of the “blast” is going out the muzzle away from you. In other words, if you are standing to the side while someone shoots, you may get a “louder” dose than if you are the shooter and all the sound and fury is going downrange.
