FPE needed to deform a pellet???

I love how we discuss our air rifle performance like mini high power rifles, but I see the term (hydrostatic shock) used a lot in here and in some videos made by prominate writers. The fact of the matter is hydrostatic shock doesn't occur until velocities reach 2,600 fps. Love the topic and feedback regardless 😉
And where did that number come from? Plenty of evidence that lower velocity projectiles have the same basic affect.
 
Hydrostatic shock remains an unsettled concept at any worldly velocity, let alone with subsonic projectiles like those fired from an airgun.

By hydrostatic shock I mean damage to the nervous system or organs or blood vessels at some useful distance from the projectile’s wound channel. As distinguished from local damage in the region surrounding a projectile’s path through tissue.
 
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And where did that number come from? Plenty of evidence that lower velocity projectiles have the same basic affect.
Dr. Robert Fackler while studying the effects of high power rifle rounds specifically the 5.56mm Nato aka 223 Remington as well as the 7.62 Nato aka 308 Winchester (Hydrostatic shock is the controversial concept that a penetrating projectile (such as a bullet) can produce a pressure wave that causes "remote neural damage", "subtle damage in neural tissues" and "rapid incapacitating effects" in living targets.) Our air rifles as well as slower moving powder burners produce localized trauma. This is a rabbit hole I don't wish to go down, but I can assure you air rifles do not produce hydrostatic shock.
 
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The Alphabet org exhaustive report on handgun performance also states that hydrostatic shock does not happen with handguns. Their velocity is similar to airguns. That conclusion is based upon a lot of research including examination of dead people.

The reason is not complicated. To create hydrostatic shock the round has to move the animal tissue faster than it can withstand without damage. That in turn requires a high power projectile. The exact lower limit may have some controversary around it, I've read 2000 fps before, but the ambiguity is not enough to mean hydrostatic shock happens with airguns (or handguns). Airguns make holes. We can make a little wider hole with an expanding projectile but that reduces penetration significantly. The size of our holes is, fortunately, pretty large relative to the size of the small game we target so making a hole in the right place is all we need to do to get a clean quick kill.
 
The Alphabet org exhaustive report on handgun performance also states that hydrostatic shock does not happen with handguns. Their velocity is similar to airguns. That conclusion is based upon a lot of research including examination of dead people.

The reason is not complicated. To create hydrostatic shock the round has to move the animal tissue faster than it can withstand without damage. That in turn requires a high power projectile. The exact lower limit may have some controversary around it, I've read 2000 fps before, but the ambiguity is not enough to mean hydrostatic shock happens with airguns (or handguns). Airguns make holes. We can make a little wider hole with an expanding projectile but that reduces penetration significantly. The size of our holes is, fortunately, pretty large relative to the size of the small game we target so making a hole in the right place is all we need to do to get a clean quick kill.
Frankly I'm glad air rifles don't produce hydrostatic shock because otherwise there wouldn't be anything left to eat LMAO :ROFLMAO:
 
Pete,

thanks for your detailed response.
● First of all, you are a great shot, killing rabbits with such a small caliber at such long ranges! 👍🏼

I have a lot to learn, I must say.
And I'd love to have rabbits to hunt down here in Peru! 😆


The best hollow point performance I have found comes from slugs around the 30fpe mark.
That is probably because they are pushed faster than pellets and some have very deep hollow points.

Interesting! 👍🏼 — Now you have me guessing if that's 30FPE in .177cal — or 30FPE in .22cal — which makes a big difference in the maybe most critical factor that makes a hollow point (HP) expand: velocity, more precisely, impact velocity.
❓ So, what caliber slug is it?

❓ And: What brand/model slug is it?
(Unfortunately, not all slugs have attempted to provide a deep HP, and some might use more pure (read, more soft) lead.




In my experience most pellets don’t mushroom. — They might flatten slightly or deform a little. I shot many tins of JSB Hades in .22 at around 25FPE, and even they don’t mushroom.

Yes, the Hades at the muzzle with 25FPE goes at 840fps. Assuming a BC of 0.023 we get
the following impact velocities at different ranges:
0y: — 840fps
8y: — 800fps
15y: — 771fps
20y: — 750fps
25y: — 730fps
30y: — 711fps


Let's look at some expansion tests I found on the internet:
Hades at impact velocity 775fps.
➠ Still a fairly good HP expansion: 29%

Projectile Test. PT012.  Leatherman (2020). -Ground Hog, Live.- 21FPE. Hades @775fps. 01.jpg




Hades at impact velocity 715fps.
➠ Now only a lousy HP expansion: 7%


Projectile Test. PT018.  GunPowder&AirPower (2019). -Gel 20percent – c. 5cm Thick.- 18,36FPE. ...jpg



🔺 As can be seen, at lower impact velocities there is little HP expansion.


🔺 The list of the ranges and velocities shows that this pellet looses velocity fast! This is the problem with hollow point pellets: no matter how fast you shoot them, they slow down in a hurry — and thus do not expand a longer ranges.
Slugs, on the other hand, due to their much higher BC, can obtain a high impact velocity for much farther out, and thus will still expand (if other factors are also favorable: soft lead, deep and wide hollow point).



Sorry for nerding out on this, it's just fun! 😆
Cheers,

Matthias
 
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Dr. Robert Fackler while studying the effects of high power rifle rounds specifically the 5.56mm Nato aka 223 Remington as well as the 7.62 Nato aka 308 Winchester (Hydrostatic shock is the controversial concept that a penetrating projectile (such as a bullet) can produce a pressure wave that causes "remote neural damage", "subtle damage in neural tissues" and "rapid incapacitating effects" in living targets.) Our air rifles as well as slower moving powder burners produce localized trauma. This is a rabbit hole I don't wish to go down, but I can assure you air rifles do not produce hydrostatic shock.
Its been a while but Im pretty sure that is with fmj. Apples to oranges. In any case, the term, and affects are more subjective than how JFK died. Most people on the internet refer to HS as causing some kind of tissue damage in addition to the physical contact from a projectile. You might not think there is enough damage to call it HS, but its silly to say the pressures involved dont do any damage. And we can debate this to the end of time and never agree. You are making a claim that it doesnt happen, and some how you know for sure. You obviously want to dive head first into this rabbit hole, since you brought up an old thread just to stir the pot lol.
 
Pete,

thanks for your detailed response.
● First of all, you are a great shot, killing rabbits with such a small caliber at such long ranges! 👍🏼

I have a lot to learn, I must say.
And I'd love to have rabbits to hunt down here in Peru! 😆




Interesting! 👍🏼 — Now you have me guessing if that's 30FPE in .177cal — or 30FPE in .22cal — which makes a big difference in the maybe most critical factor that makes a hollow point (HP) expand: velocity, more precisely, impact velocity.
❓ So, what caliber slug is it?

❓ And: What brand/model slug is it?
(Unfortunately, not all slugs have attempted to provide a deep HP, and some might use more pure (read, more soft) lead.






Yes, the Hades at the muzzle with 25FPE goes at 840fps. Assuming a BC of 0.023 we get
the following impact velocities at different ranges:
0y: — 840fps
8y: — 800fps
15y: — 771fps
20y: — 750fps
25y: — 730fps
30y: — 711fps


Let's look at some expansion tests I found on the internet:
Hades at impact velocity 775fps.
➠ Still a fairly good HP expansion: 29%

View attachment 397711



Hades at impact velocity 715fps.
➠ Now only a lousy HP expansion: 7%


View attachment 397713


🔺 As can be seen, at lower impact velocities there is little HP expansion.


🔺 The list of the ranges and velocities shows that this pellet looses velocity fast! This is the problem with hollow point pellets: no matter how fast you shoot them, they slow down in a hurry — and thus do not expand a longer ranges.
Slugs, on the other hand, due to their much higher BC, can obtain a high impact velocity for much farther out, and thus will still expand (if other factors are also favorable: soft lead, deep and wide hollow point).



Sorry for nerding out on this, it's just fun! 😆
Cheers,

Matthias
You didn't nerd it out any worse than I did LOL:geek: