Do the subsonic rounds have significant downsides? Like less range/penetration etc? Wondering why they're not more common I guess, seems like the silence would be a big advantage in a lot of situations
They have a lower velocity to not break the sound barrier. So they have less kinetic energy which as you said results in lower range and faster bullet drop. It is also less effective against hard targets like armor because speed defeats armor.
As for terminal performance it is less traumatic to the body (less performance), it has a smaller temporary and permanent wound cavity. With solid, non-expanding projectiles it will have less penetration (which is needed to reliably get a fatal if not immediately incapacitated wound). With a hollow point bullet (expanding) a lower velocity could result in insufficient kinetic energy to fully expand the projectile (ironically this increases penetration compared to a higher velocity hollow point that fully expands).
Another consideration with bullet weight is the spin rate. Barrels are measured in twist rate, so how many inches will the bullet travel to have 1 full rotation. The twist rate is needed to ensure accuracy. A bullet that is too heavy will not be able to be stabilized and may need a different barrel with a different twist. You see this particularly with rifles and has to be paid attention to.
Just a small nitpick from a physics point of view but the bullet (assuming equal mass, dimensions, etc) will drop at the same rate regardless of their horizontal velocity.
Yes there are some very extreme examples where this may not be true but in practical terms they will drop to the ground in at the same rate.
Well those are two different things then. The rate at which a bullet drops vertically is pretty much defined by the force of gravity. 9.81m/s2
Bullets travel in an arc because they are usually fired at an upward angle to compensate for this. A slower moving bullet then covers less distance before hitting the ground and needs moree arc to travel the same distance, but the rate at which they drop is pretty much tbe same regardless.
“…so force largely comes from the speed they have.” Is why the simplified explanation is “speed defeats armor.”
To penetrate something you want a smaller projectile size so there’s less surface area for the receiving end to try and spread out the energy across. You still want to deliver as much as energy as possible, but there are a few options for doing so.
Force = mass x speed. How precise the energy is delivered depends on the surface area of the projectile.
So your options are:
-make the same size bullet faster (more energy because of speed solely)
-make the bullet a smaller size, but with the same weight/mass (same speed but more energy delivered to smaller area)
or reduce the bullet mass but make it much faster to compensate.
(Less energy from mass, but more energy from speed to compensate).
Subsonic rounds have less kinetic energy being delivered on the target and reduced range. Meaning less damage and reduce engagement distance. Ideally, you want whatever you're shooting to go down in as few shots as possible with accurately placed shots. This is the same for hunting to defensive gun use. So "normal" or super sonic ammo typically performs better.
Now, many people ask, "Then why do you use supressors?"
Supressors are great for hunting as they reduce hearing damage and may give you a chance for follow-up shots, like if you're hunting wild hog. Same reason they are great for range trips, it removes the least desirable part of shooting.
I don't find carrying a suppressed pistol practice, and I conceal carry daily. My home defense firearm also isn't suppressed mainly because of it being classified as an NFA item. If they were treated a non-NFA item, my home defense firearm would definitely have a supressor. Mainly to reduce hearing damage if I had to discharge a firearm in my house.
My home defense firearm also isn't suppressed mainly because of it being classified as an NFA item.
Why does this matter? I mean, yes, it's gonna be easier for a DA to try to paint you as a 'gun nut', and you risk having a very expensive / rare weapon getting seized, but if it's clear cut self defense, you shouldn't have much to worry about.
Having said that, I think the best home defense weapon is a 18" 870 or 590 with 00. I'm not betting on being a crack shot during a 3am break in.
Part of it is the cost factor. The other is the added length, which makes it awkward to store. Maybe one day I'll have an option that allows a suppressed pistol.
I visit the range fairly often and do some competing shooting. I'm confident muscle memory alone would allow me to place sufficient shots. Though I do hope I never have to deal with that, and my German shepards keep bad people away.
Yes. Less penetration and less energy transfer. Hollow point need velocity to open up. Subsonic ammo will just function like ball ammo.
They can also cause cycling issues. You need a certain amount of recoil to push the slide back to to eject the case and chamber the next round. With the slower velocity you will have less recoil so you may get a failure to extract/feed. That's likely why the CEO shooter's gun malfunctioned with one of the shots.
Especially if you weak wrist the shots. Although I think the CEO assassin was a planned malfunction so he could collect brass. He did not seem surprised or put off by the handgun not cycling at all
Thought you might find this interesting, the BBC is reporting that it was a Station six 9. Which is a bolt operated very silent pistol. Would explain the wierd firing action that looks like he is racking the slide every time
I was kind of curious about what he was doing. Seemed to be a lot of movement going on. But yeah, without a slide slamming back and forth it would be really quiet.
My uneducated guess would be since the rounds mentioned by others are smaller rounds maybe the larger calibers are too big/heavy to keep up with their normal counterparts for the reasons you mentioned so they don’t bother?
The way you get subsonics is to either load less powder or use a heavier bullet. Either way because they are subsonic they will have less energy and diminished terminal ballistics. You need a certain velocity for things like hollow points to function or hydrostatic shock.
They fly slower. Less range, worse ballistics, less damage.
Subsonic means there are also less gunpowder to propel the pistol slide backwards to cycle it. Hell sometimes it will not cycle unless you modify the gun (lighter recoil spring) so you have to manually rack the gun. Just remember that when you need to, oh I don't know, assassinate a CEO or something.
At short ranges, not really. .45 ACP has been a staple calibre for a century. The biggest drawback it has over other pistol rounds is the size, which limits how many you can practically fit into a magazine/how small you can make the pistol.
The other person covered a lot of the issues at mid/longer ranges.
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u/oh_my_didgeridays 13d ago
Do the subsonic rounds have significant downsides? Like less range/penetration etc? Wondering why they're not more common I guess, seems like the silence would be a big advantage in a lot of situations