Here's some information on atmospheric overpressure which I provided 23 May 2025,
This is Mark Ouellette’s bailiwick. Perhaps he can weigh in on over pressure and concussive energy.
Thanks Jay
@Altitude sickness I may not be a scientist but I've assisted many on development projects...
Muzzle Blast compresses the air or atmosphere around us causing atmospheric overpressure. For a brief amount or time, this is much like the water pressure undersea. Now let’s put this into even simpler terms.
Most people have experienced a far too loud stereo with its bass tones set to maximum. We feel every bump and thump enough to give us headaches. Why, because the...
"I may not be a scientist but I've assisted many on development projects...
Muzzle Blast compresses the air or atmosphere around us causing atmospheric overpressure. For a brief amount or time, this is much like the water pressure undersea. Now let’s put this into even simpler terms.
Most people have experienced a far too loud stereo with its bass tones set to maximum. We feel every bump and thump enough to give us headaches. Why, because the stereo speakers compressed the air which in turn decompressed in our direction. Thump, thump, thump against our heads.
What we feel is not only the sound in our ears, which also is caused by atmospheric overpressure, the overpressure affects our entire bodies. But perhaps most or all, our brains that float in fluid. “Inside the skull, the brain floats in a jelly-like substance called cerebrospinal fluid (CSF). CSF protects, nourishes, and cleans the brain.”
https://www.brainfacts.org/diseases...e-watered-down-brain-and-hydrocephalus-102620
A fast push of over pressured air against the human body can cause a brain to move within the fluid. With enough of an atmospheric push, a brain could bounce of the inside of its skull. This occurs with an underbody blast when a vehicle hits a mine. Shrapnel rips the bottom of the vehicle apart and pushes the vehicle upward. Faster than the physical force moving upward is the supersonic shock wave of the high explosive of the mine. That shock wave, yes really high and fast moving overpressure, goes through our bodies. Similarily, one "feels" artillery.
Now let’s consider the think about the atmospheric over pressure from muzzle blast or our big bore rifles. Sound which is overpressure, is measured in decibels. Most rifles produce around 165 decibels,
https://proears.com/loudest-guns/ Sound intensity doubles every 3 db because decibels since the increase is logarithmic rather than linear.
https://audiochamps.com/is-3db-or-6db-twice-as-loud/
Decibles are a measure in amplitude. What most are unaware of is that sound also has duration. How long a sound or atmospheric overpressure last also affects humans. I don’t have a reference but from the research range, the total effects of overpressure of a weapon increase with the square of the bore. The bigger the bore, the more overpressure. If a .30 produces a level or 9, a .40 produces a level of 16, and a .50 produces a level of 25. These numbers are a sophisticated wild ass guess (SWAG), but hopefully you understand.
US Soldiers are only allowed in training to shoot a maximum of three rockets or missiels per day,
https://en.wikipedia.org/wiki/Shoulder-fired_missile , Mk 153 SMAW, Javelin, Carl Gustaf 8.4 cm recoilless rifle. Those have really large bores and high decibles blasts producing massive over pressure for a substantial to the brain amount of time. Three hits (over pressures) to the brains and humans need a rest.
For large sporting arms and their shooters, every person is a little different in their tolerance. I have found I can shoot a couple dozen shots with my .458 Win. Somedays I’ve shot near 50 times with combined .375, .416, and .458 Win. But when I shoot my .450 Rigby, ten rounds and I have a small headache.
Overall,
- Gun fit is very important to perceived recoil.
- Better shooting form will reduce stress and pain on the body.
- A heavier rifle recoils less than a lighter rifle if all else is the same.
- Longer barrels will reduce felt muzzle blast (over pressure) somewhat.
- Larger bores produce longer duration overpressure.
- Muzzle breaks are obnoxious. They release pressure laterally from the bore and closer to the shooter.
- And each and every person is a little different. Shoot the more powerful rifle you can shoot accurately and that doesn’t punish the body each and every shot!"
