How loud is the supersonic crack?

Status
Not open for further replies.
Standing in the target pits, I find the supersonic crack of a 6.5-.284, .308, or .30-06 fired from 600 yards to be fully the equivalent of a .22lr handgun fired next to me. I find it intolerable without hearing protection.
Click to expand...

I concur. I likened it to a 45 going off about fifteen feet away,though. The very first time I worked the pits, I wondered why everyone had hearing protection.

First shots, I knew why.

Thing I remember most, visually, was the little flakes of paper, black on one side, white on the other, floating down in the morning sun, kinda blinking on-off as they fluttered down in the light.



Vibe, thank you for digging up that excellent information.
 
Thing I remember most, visually, was the little flakes of paper, black on one side, white on the other, floating down in the morning sun, kinda blinking on-off as they fluttered down in the light.
Click to expand...
I recall taking my turn in the pits during the 1,000 yard events at Camp Perry on the points where people didn't know how much to come up on their sights to get to 1,000 yards. Instead of a "crack, thump", you'd hear "thud, thump" when instead of breaking the sound barrier overhead, followed by the sound of the shot, the bullet would hit the sandbag or the berm, followed by the sound of the shot. In those isntances you'd often have sand in your hair and close where the bullet cut the sandbags.

A friend was there for an Ohio Rifle and Pistol Association 1,000 yard "fun shoot" that a bunch of .45-70 shooters attended. He said that instead of "crack, thump", you'd hear "whizz, slap, clunk, boom" as the 300-500gr. bullet would go overhead at subsonic speed, followed instantly by the bullet hitting the target at an acute angle, followed by the bullet penetrating the tin roof of the target shed (which at the time was immediately in front of the pits), followed by the sound of the shot.
 
I recall taking my turn in the pits during the 1,000 yard events at Camp Perry on the points where people didn't know how much to come up on their sights to get to 1,000 yards.
Click to expand...

IIRC, I had to go up about 34 clicks on the sight of a Garand. Looked like an antenna, sticking up there. As someone else reported recently as to how he did it, a buddy of mine and I also went up to the Grasslands and tediously measured out 1000 yards with a 100 foot tape, and he hid behind a hillock near the target with binocs and reported strikes by walkie-talkie.

Dialed it right in.
 
Jets at air shows routinely have on jet at some point go supersonic and create a sonic boom.

It is pretty rare to fly near Mach 0.95 without going above the speed of sound since aircraft operating at Mach 1.0 is very difficult and dangerous.

From about Mach 0.95 to around 1.05 buffeting is severe and the controls are less than smooth (as Chuck Yeager found out many years ago).

As the air flow over portions of the plane exceeds the speed of sound the shock waves form and then attach.
The Bernoulli equation stops to work since it does not allow for the standing pressure waves generated by faster than sound media speeds.

Aircraft usually accelerate through Mach 1.0 as quickly as possible. Shallow dives can even be used to minimize the time spent in the transonic region.
 
didnt read the other posts but an easy way to think of it is that a bull whip that "cracks" is actually a miniature sonic boom. So Something quite small can be pretty loud. Sounds like a small firecracker.

The tip of the whip can easily exceed the speed of sound.
 
I have a pellet gun the can make pellets go supersonic, they are not loud, i actually enjoy the sound, it sounds like a .22 but Im sure that a bigger caliber rifle will be much louder.
 
What's interesting is the variety of sounds bullets make. As Jim K can attest, when working the pits at a high power match, you begin to be able to tell if the round is coming in super versus sub sonic, stable versus tumbling, and even relative distance all by the sound they make. You also learn to hug the wall real quick when you here the 'pzzzzyt' sound when a round clips the steel target frame! I saw one hit the ground no more than 5 feet away not too long ago! Oh yeah.... Good idea to keep that info from your wife! Otherwise you'll find your 'honey do' list surprisingly long the morning of the next match!
 
AnthonyC mentioned:
I have a pellet gun that can make pellets go supersonic, they are not loud. i actually enjoy the sound, it sounds like a .22 but Im sure that a bigger caliber rifle will be much louder.
Click to expand...

If this is a regular old pellet gun, not designed to shoot those new light pellets over the speed of sound, it may be an indication that you are using too much oil in the piston or the wrong kind.

Too much oil can result in "dieseling" in the piston chamber (where the oil spray or vapor ignites) and cause the pressure to go too high, damaging the seals.

I've got an old Feinwerkbau where this dieseling happens if I get too generous with the oil. Smells like a diesel truck when it goes off. Don't know if the lead pellets are going supersonic, but the sound is much louder than normal.
 
Artiz said:
I can assure that, a couple of months ago there was the Quebec Air Show, this was the greatest air show ever, Blue Angels, Thunder Birds, Red Arrows, Snow Birds, and the Canadian Demo CF-18 who was supposed to fly just under the sound barrier, unfortunately, this nice pilot broke it just a little and released the gas at time, because we saw the "white cone" sourrounding the aircraft, mannn... add to the sound of a flying F-18 a broken sound barrier, you get hands on ears, omg that was loud, really loud.
So a bullet creating a shockwave is NOTHING.
Click to expand...
Size matters, of course, in bullets as well as planes. The sonic boom from an FA-18 pales in comparison to that of an F-4 or even an F-14. We witnessed several sonic booms over the Detroit River just a few weeks ago during the Gold Cup quals. 2 FA-18s from an eastern demo team put on a rather cool show. But nothing like the old days of air shows. And an SR-71 lays down a horrendous sonic boom even at 80,000 feet. In size, compared to a fighter jet, it is gigantic. If you could completely quiet the muzzle blast of a .460 Weatherby, I'm sure it would be far louder than a suppressed 5.56 Nato.
 
AnthonyC mentioned:

Quote:
I have a pellet gun that can make pellets go supersonic, they are not loud. i actually enjoy the sound, it sounds like a .22 but Im sure that a bigger caliber rifle will be much louder.

If this is a regular old pellet gun, not designed to shoot those new light pellets over the speed of sound, it may be an indication that you are using too much oil in the piston or the wrong kind.

Too much oil can result in "dieseling" in the piston chamber (where the oil spray or vapor ignites) and cause the pressure to go too high, damaging the seals.

I've got an old Feinwerkbau where this dieseling happens if I get too generous with the oil. Smells like a diesel truck when it goes off. Don't know if the lead pellets are going supersonic, but the sound is much louder than normal.
Click to expand...

Its not an old gun, its a new Gamo Big Cat, The pellets came with the gun, and I dont think I am going to be feeding my pellet gun a steady diet of supersonic pellets.
 
i would think that its volume would be in direct relationship to its size. a bullets sonic boom would be much less than a jet airplane, which would be much less than the spce shuttle, which would be much less than a 2 mile diameter asteroid. in many cases, SIZE DOES MATTER!
 
Status
Not open for further replies.

Similar threads

K
  • Locked
The fact about supressors
Replies
7
Views
1K
entropy
entropy
J
  • Locked
Supersonic crack question
Replies
17
Views
4K
Zoogster
Z
G
  • Locked
How many feet per second is the speed of sound?
2
Replies
40
Views
29K
matrem
M
Demi-human
  • Locked
A side question about the sound.
Replies
21
Views
1K
Ranb
Ranb
A
  • Locked
Why do big box store carry Remington .300 Blackout ammo in supersonic but not Subsonic?
2 3
Replies
59
Views
3K
Aim1
A
Back
Top