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this post was submitted on 18 Jul 2026
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So they say that the Army uses 4 PSI as a placeholder safety threshold while they gather data on this specific issue, but do say that threshold is based on prior not directly related research.
The .50 BMG is obv in a class of its own (completely smashing that threshold), but the only one that tickles at that threshold is the Desert Eagle (also a .50 caliber round).
Most of the firearms they tested rated in in the 1-2 PSI range....and as I was double checking that noticed their note: "Measurements shown are the average of the three highest readings for weapons fired from inside a range booth."
I don't mean to say there's nothing here, but this does feel alarmist. Nonetheless does seem like double hearing protection wouldn't be a bad idea.
It is interesting that a Model 1911 clocked in with a lower pressure wave than a "9mm pistol" (wonder which model(s) they tested). John Browning continues to flex from the grave.
A 50ae from a desert eagle doesn't get anywhere close to that of a 50bmg. It's about 15% of the energy, if even, which is about the same as typical infantry rifles.
Caliber is probably is among the worst metrics for determining energy honestly
Came here to say this.
.50 AE and .50 BMG are worlds apart. Hell, even the difference between .45 ACP and .45-70 is pretty big.
The 1911 uses .45 and .45 is a subsonic ammunition, which means its muzzle velocity is below the speed to break the sound barrier, and doesn't produce a supersonic crack. The delisle carbine was a bolt action integrally suppressed rifle made from the Lee Enfield, re-chambered for .45 from .303 due to its subsonic nature and is known to be one of the quietest firearms to exist, and the round doesn't produce a loud crack.
Where 9mm isn't subsonic, it has a higher muzzle velocity and therefore would generate more atmospheric pressure, and a supersonic crack. This is why the world famous MP5SD, known for its total silence, was revolutionary. people say the only thing you hear is the bolt cycling. It has a perforated barrel that leaks enough of the gases out of the barrel into the suppressor. Infact, it leaks enough to actually prevent the 9mm from achieving supersonic speeds. They designed it this way so it doesn't have to use ammunition that is specifically filled to be subsonic, or to use a round that is inherently subsonic like .45.
So that is two examples of gun design history around trying to be quiet with ammunition, one designed around the ammo, and one around the gun.
4 psi is based on the army report for popping ear drums, more specifically for impact events like gun shots. Note, your ears can handle 4 psi if it's a slow ramp up so they can acclimate like diving in water.
I agree that it does feel alarmist, but to be fair, the article mentioned multiple times that the research isn't established just yet. In the end it sort of reminds me of the radiation doses from x-rays and CT scans. You have to weigh the potential risks with the potential benefits when deciding to practice with a firearm.
In the range I've always worn double, though that only provides incremental increase in protection.
With double, I barely notice any typical round - it really is just background noise, though you can feel the pressure in your chest.
But something like a DE? Holy hell that was something else. WOOMP! I think you really feel even that more than you hear it.
This article seems like a tempest in a teapot.