Subsonic, supersonic? What...

Millie

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I can't understand, from what I've read, about slower vs faster rounds. Do the slower ones stay in what you shoot and the others don't. You guys are good at 'splainin' stuff to me in simple-ish words, so have at it! (The articles assume I already know a lot! Lol. We all know I don't....)
 
Supersonic is anything traveling over 1,125 feet per second. One easy way to tell super vs sub is the sonic crack, think 45acp vs .223.

It's more important when talking about suppressors. Generally you want to shoot subs through a suppressor to keep things as quiet as possible. Even the best suppressor in the world can't remove the sonic crack that will happen once the bullet leaves the barrel and reaches 1125ft/sec.
 
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I can't understand, from what I've read, about slower vs faster rounds. Do the slower ones stay in what you shoot and the others don't. You guys are good at 'splainin' stuff to me in simple-ish words, so have at it! (The articles assume I already know a lot! Lol. We all know I don't....)


Don’t over think is Millie. Sub-sonic just means they don’t break the sound barrier.

When a gun is fired you basically hear three noises, the Action cycling, the powder igniting, and the bullet breaking the sound barrier.

So a lot of people like sub-sonic Bullets when shooting with a suppressor because it removes one of the three noises which makes them even quieter.

Sub-sonic just means slower. It can mean less penetration, but that is usually just a side effect and not the intended purpose.


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Supersonic is anything traveling over 1,125 feet per second. One easy way to tell super vs sub is the sonic crack, think 45acp vs .223.

It's more important when talking about suppressors. Generally you want to shoot subs through a suppressor to keep things as quiet as possible. Even the best suppressor in the world can't remove the sonic crack that will happen once the bullet leaves the barrel and reaches 1125ft/sec.
Don’t over think is Millie. Sub-sonic just means they don’t break the sound barrier.

When a gun is fired you basically hear three noises, the Action cycling, the powder igniting, and the bullet breaking the sound barrier.

So a lot of people like sub-sonic Bullets when shooting with a suppressor because it removes one of the three noises which makes them even quieter.

Sub-sonic just means slower. It can mean less penetration, but that is usually just a side effect and not the intended purpose.


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Thanks, guys!
 
FYI, some rounds are inherently sub sonic like the .45 ACP. Your garden variety 115 gr 9mm is supersonic. That said, the only reason ammo is listed as subsonic is if you are using a heavier than standard bullet or a light powered charge to slow it down. That's a selling point for the suppressor guys. In other words, don't go out of your way to buy ammo that says subsonic on it. And if the standard ammo is inherently subsonic don't worry about it because nobody else does.
 
@Millie

Here's a gee whiz kinda video I made. It's a 9mm AR, with and without a suppressor. The magazine is loaded with three different kinds of ammo, in a repeated rotation.

1st shot: 115gr
2nd shot: 124gr
3rd shot: 147gr

And that repeats over and over. Only the 147gr is subsonic. You won't hear a huge difference without the suppressor (the first two sets of shots), but with the suppressor it's a drastic difference. You can also see how the subsonic burns with streaks more than a big blast with the unsuppressed shots.



As B00ger mentioned, there are three noises. The subsonic ammo eliminates one of them. The suppressor greatly reduces another. The majority of the sound you hear with the suppressed 147gr shots are just the action of the firearm itself...which would be similar to what you'd hear when pulling the charging handle and letting go on an AR, racking a slide on a semi-auto pistol or manipulating the action on a pump shotgun, etc.

iPhone mics and YouTube audio is definitely not real-world, but it's close enough that video is a good representation as to how much difference ammo can make in the perceived noise.

At a distance, subsonic sounds very different because there's no sonic crack wave with the projectile as it flies.
 
FYI, some rounds are inherently sub sonic like the .45 ACP. Your garden variety 115 gr 9mm is supersonic. That said, the only reason ammo is listed as subsonic is if you are using a heavier than standard bullet or a light powered charge to slow it down. That's a selling point for the suppressor guys. In other words, don't go out of your way to buy ammo that says subsonic on it. And if the standard ammo is inherently subsonic don't worry about it because nobody else does.

That right there ^^^

If anyone is looking at 9mm 147gr - here you go.

https://www.bonefroggunclub.com/col...ts/9mm-147gr-american-eagle-fmj-1000rds-ae9fp

Screenshot_20171019-082511.png
 
Ugh
b8e89515c5da422793259257aff1406c.jpg
 
As far as staying in what you're shooting, faster doesn't mean anything. A 17 hmr is faster than a 45-70. The 45-70 has more penetration potential that the 17. Bullet type ie cast lead, full metal jacket, hollow point, so fourth and so on makes a difference. So does what part of the body is hit. How thick is your target? What is it? Wood, human, deer? Man sized? 45acp is normally subsonic and is most definitely capable of going through and through human sized game.

Are we talking 38 special? 38 special is a proven round. 38 special is called that because it was a magnum round before they came up with calling magnums, magnums. The magnum part comes from a magnum of wine. Magnum meaning more wine and the 357 magnum is really a super magnum. So 38 special is a good man stopper in standard pressures with a good quality bullet. If you like more power go plus p (+p) if your gun is safe to do so. In a fire fight none of that will make much difference shoot the bastard with a good bullet, twice. If that doesn't work shoot some more.


A little more history on 38 special and 357 mag. When S&W made the 38 special it was special because it was 38 long colt but more powerful. Then came 357 mag but they didn't know what to call it. On guy said I like magnums of wine so the rest is history.
 
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As far as staying in what you're shooting, faster doesn't mean anything. A 17 hmr is faster than a 45-70. The 45-70 has more penetration potential that the 17. Bullet type ie cast lead, full metal jacket, hollow point, so fourth and so on makes a difference. So does what part of the body is hit. How thick is your target? What is it? Wood, human, deer? Man sized? 45acp is normally subsonic and is most definitely capable of going through and through human sized game.

Are we talking 38 special? 38 special is a proven round. 38 special is called that because it was a magnum round before they came up with calling magnums, magnums. The magnum part comes from a magnum of wine. Magnum meaning more wine and the 357 magnum is really a super magnum. So 38 special is a good man stopper in standard pressures with a good quality bullet. If you like more power go plus p (+p) if your gun is safe to do so. In a fire fight none of that will make much difference shoot the bastard with a good bullet, twice. If that doesn't work shoot some more.


A little more history on 38 special and 357 mag. When S&W made the 38 special it was special because it was 38 long colt but more powerful. Then came 357 mag but they didn't know what to call it. On guy said I like magnums of wine so the rest is history.
The instructions on my gun specify NO +p rounds.....maybe because it's called ultra lite and can't handle extra pressure? I don't have a clue...just no on the +p! Lol. I have hollow points for defense, fmj to practice.
 
The instructions on my gun specify NO +p rounds.....maybe because it's called ultra lite and can't handle extra pressure? I don't have a clue...just no on the +p! Lol. I have hollow points for defense, fmj to practice.
Listen to you using ALL that jargon like a pro!
 
The instructions on my gun specify NO +p rounds.....maybe because it's called ultra lite and can't handle extra pressure? I don't have a clue...just no on the +p! Lol. I have hollow points for defense, fmj to practice.
And that'll do just fine. Are you worried about over penetration?
 
@Millie

Here's a gee whiz kinda video I made. It's a 9mm AR, with and without a suppressor. The magazine is loaded with three different kinds of ammo, in a repeated rotation.

1st shot: 115gr
2nd shot: 124gr
3rd shot: 147gr

And that repeats over and over. Only the 147gr is subsonic. You won't hear a huge difference without the suppressor (the first two sets of shots), but with the suppressor it's a drastic difference. You can also see how the subsonic burns with streaks more than a big blast with the unsuppressed shots.



As B00ger mentioned, there are three noises. The subsonic ammo eliminates one of them. The suppressor greatly reduces another. The majority of the sound you hear with the suppressed 147gr shots are just the action of the firearm itself...which would be similar to what you'd hear when pulling the charging handle and letting go on an AR, racking a slide on a semi-auto pistol or manipulating the action on a pump shotgun, etc.

iPhone mics and YouTube audio is definitely not real-world, but it's close enough that video is a good representation as to how much difference ammo can make in the perceived noise.

At a distance, subsonic sounds very different because there's no sonic crack wave with the projectile as it flies.

Cool video...thanks!
 
And that'll do just fine. Are you worried about over penetration?
The reading I did said hollow points will do more damage if I have to shoot someone. I really sincerely pray that I never do, but if so I want to be sure they cease to be a threat! Hate to sound so bloodthirsty, but this is a crime heavy area, considering we're in the boonies. I've had a person on the property a couple of times late at night, but the motion sensor lights made them leave! Very scary!
 
I see you heading for the "over-penetration" rabbit hole that will lead so far out into the weeds of detailed ballistic data that you'll forget what the question was.
For me over-penetration is a non-issue BECAUSE: You have to assume anything you shoot might miss or might go through your target.
Therefore be aware of your target and what is behind it instead of over-thinking the ballistics.
 
The reading I did said hollow points will do more damage if I have to shoot someone. I really sincerely pray that I never do, but if so I want to be sure they cease to be a threat! Hate to sound so bloodthirsty,


Hollow points are great for stopping people. Not all are created equal. There is great research out there so look up how they perform out of your gun, barrel length and all that.

Bloodthristy is me during hunting season, Dracula, and the guy who intends to harm you.
 
The instructions on my gun specify NO +p rounds.....maybe because it's called ultra lite and can't handle extra pressure? I don't have a clue...just no on the +p! Lol. I have hollow points for defense, fmj to practice.
IMO and by no means I am an expert, you should still shoot several rounds of your hollow point just so you get the feel of firing hollow point rounds.
 
I see you heading for the "over-penetration" rabbit hole that will lead so far out into the weeds of detailed ballistic data that you'll forget what the question was.
For me over-penetration is a non-issue BECAUSE: You have to assume anything you shoot might miss or might go through your target.
Therefore be aware of your target and what is behind it instead of over-thinking the ballistics.
I did see some videos of shots going thru various things, and if I do have to shoot, I don't want holes in my wall, so I hope to get to be a good shot and pray I don't have to point a gun at a person, ever....
 
IMO and by no means I am an expert, you should still shoot several rounds of your hollow point just so you get the feel of firing hollow point rounds.
I hope to to just that after my qualifying on Sunday. I'm Hoping the instructor will let me have some time , if not I will get to a range somewhere!
 
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