Retained energy - .22 vs .177

[rabbitwrecker]

With any sub-12 ft/lb air rifle, all this talk of retained energy, 'knockdown' power and the like is utterly meaningless without pin-point placement...

[harvey_s]

And any talk of pin-point accuracy is pointless without learning your trajectories, granted one is less demanding than the other at longer ranges - but without practice neither is any good

[Artfull-Bodger]

With any sub-12 ft/lb air rifle, all this talk of retained energy, 'knockdown' power and the like is utterly meaningless without pin-point placement...

there's a fallacy that heavier pellets hit harder, take a look at this test-

https://www.youtube.com/watch?v=OJX3xg1nUAY

You will note the faster pellet creates a larger wound channel and the wadcutters and hollowpoints transmit the most impact force, a lighter high velocity pellet is not only superior in it's less range critical, but it has greater impact creating a larger cavity, when your messing about with power as low as 5-7ftlbs at the target 1ftlb makes no practical difference!

when your using power levels this low It's ALL about accuracy, add to that the greater impact of a faster pellet and the choice is self explanatory.

[rhyslightnin]

there's a fallacy that heavier pellets hit harder, take a look at this test-

https://www.youtube.com/watch?v=OJX3xg1nUAY

You will note the faster pellet creates a larger wound channel and the wadcutters and hollowpoints transmit the most impact force, a lighter high velocity pellet is not only superior in it's less range critical, but it has greater impact creating a larger cavity, when your messing about with power as low as 5-7ftlbs at the target 1ftlb makes no practical difference!

when your using power levels this low It's ALL about accuracy, add to that the greater impact of a faster pellet and the choice is self explanatory.

One thing that gets me with these tests is that terracotta wax just isn't flesh & bone... Just simply down to the fact you can mold it with your hands means it's very different. So I don't understand how this can be used as a reliable test substrate at all, it's bound to react differently to a pellet passing through than a rabbits head.

It's a bit like saying I'm going to test this rope strength using a different type of rope to the one I'm doing the test for !!!!??

[Artfull-Bodger]

One thing that gets me with these tests is that terracotta wax just isn't flesh & bone... Just simply down to the fact you can mold it with your hands means it's very different. So I don't understand how this can be used as a reliable test substrate at all, it's bound to react differently to a pellet passing through than a rabbits head.

It's a bit like saying I'm going to test this rope strength using a different type of rope to the one I'm doing the test for !!!!??

A rabbits head creates even less resistance than the wax so produces even less braking effect on a heavy pellet than the wax does, so the impact velocity and the amount of energy dumped is even more important, what the wax shows, unlike ballistic gel which is elastic so closes up, is the actual cavity the pellet creates, the bigger the cavity the greater the trauma that is caused, a good example was the .20 pellet which heavier than a .177 but only slightly larger in surface area it's core was extremely small, it took most of it's energy with it, and that's exactly what you don't want, ideally you want the hollowpoint or wadcutter, but as we all know few of these pellets will group at longer ranges.

But even then, because the energy levels are so low, because the rabbit your shooting has very little resistance to the pellet, shot placement is the critical function, and the flatter flying light pellet is more forgiving than the slower more looping trajectory of the heavy, when you then add in the pellet creating more impact damage and getting there faster the choice is clear.

[rhyslightnin]

A rabbits head creates even less resistance than the waxhow do you know??? And if this is the case why is pass through more common in .177??so produces even less braking effect on a heavy pellet than the wax does, so the impact velocity and the amount of energy dumped is even more important, what the wax shows, unlike ballistic gel which is elastic so closes up, is the actual cavity the pellet creates, Only in terracotta wax which will respond in one way which is completely different to bone, flesh and as you say ballistic gel.... I really don't think it shows anything. In the delrin thread on here it has been said that turning delrin is funny as you have to cut it fast to get a good finish which is the opposite to most other materials. I really don't think that the "splash" trauma that you see in wax gives a true representation of anything other than what it is so it's highly possible it's reverse is the case when it comes to flesh & bone. You never ever see gigantic holes in rabbits heads from .177 and very rarely see there skulls cracked and soft around the wound but you do with a .22.the bigger the cavity the greater the trauma that is caused, a good example was the .20 pellet which heavier than a .177 but only slightly larger in surface area it's core was extremely small, it took most of it's energy with it, and that's exactly what you don't want, ideally you want the hollowpoint or wadcutter, but as we all know few of these pellets will group at longer ranges.

But even then, because the energy levels are so low, because the rabbit your shooting has very little resistance to the pellet, shot placement is the critical function, and the flatter flying light pellet is more forgiving than the slower more looping trajectory of the heavy, when you then add in the pellet creating more impact damage and getting there faster the choice is clear.

I think your slightly miss lead by somthing akin to false advertising here.. and I fear this happens alot.
I'm not saying that you are wrong in your conclusion at all I want that to be duely noted, I just think these tests aren't being concluded in a true analytical way that derives truth from the subject.

Rhys

[Artfull-Bodger]

I think your slightly miss lead by somthing akin to false advertising here.. and I fear this happens alot.
I'm not saying that you are wrong in your conclusion at all I want that to be duely noted, I just think these tests aren't being concluded in a true analytical way that derives truth from the subject.

Rhys

Yeah but you need to give a reason why really, not just go "I don't want to believe it"!

you have to comprehend the physics is relative to the very low energy levels we use.

The cavities are a function of the physics of the shockwaves created by impact, drop a pebble in water you get a splash and ripples, its the same principle regardless of the material, what the cavity shows is the extent the shockwave displaced the material it was shot into, change the material (heavy clay or a cow pat) and you get different sized cavities but they will remain the same relative to each other as in light to heavy, the faster a projectile impacts the greater the ripple, its also a function of surface area the greater the area the more material will be displaced.

What the weight gives you is momentum and this is why a heavier pellet penetrates further but it retains it's energy and passes through as its surface area cannot create enough drag in the material (drag = energy dump) , the whole point of a hollowpoint is to create a greater braking effect so the pellet displaces more material by using the energy it has, hence the larger cores shown!

In your head you can get the idea it's heavier therefore hits harder but in reality its surface area (the actual area that transmits the energy) is the same as a lightweight pellet, and as its travelling slower its impact is less, but its momentum is greater, it's such a complex interaction that its very hard to grasp what's happening, but the cores give a visual example of the effect, bigger cores equal more physical trauma!

The trajectory comparison however is black and white , it's indisputable that a fast light pellet is less range critical than a heavy one, and in our 12ftlbs world the small differences in trauma come second to the ability to hit where you need to.

Shot placement is everything, we don't have the energy to rely on shock damage alone.

[Muskett]

There is very little practical shock damage, even less than the wax plugs suggest as flesh is more elastic and the hydraulic shock given isn't explosive enough at these energy levels to do much. So shot placement is everything, and that shot placement has to travel through to destroy a vital organ. For instantaneous results that equates to a brain shot. Be it pigeon, squirrel or rabbit then its a small target with little room for error.
Which is why .177 rules.

Higher energies, even FAC air rifles, everything changes. At energies that hydraulic effect works then the cells are destroyed and tissue shredded within a massive wound tract. How big is all to do with energy dumped and bullet construction. Just not happening much with sub 12ft/lbs and their pellets. All too marginal.

Round head and accurate remains the best compromise.

[rhyslightnin]

Yeah but you need to give a reason why really, not just go "I don't want to believe it"!

you have to comprehend the physics is relative to the very low energy levels we use.

The cavities are a function of the physics of the shockwaves created by impact, drop a pebble in water you get a splash and ripples, its the same principle regardless of the material, what the cavity shows is the extent the shockwave displaced the material it was shot into, change the material (heavy clay or a cow pat) and you get different sized cavities but they will remain the same relative to each other as in light to heavy, the faster a projectile impacts the greater the ripple, its also a function of surface area the greater the area the more material will be displaced.

What the weight gives you is momentum and this is why a heavier pellet penetrates further but it retains it's energy and passes through as its surface area cannot create enough drag in the material (drag = energy dump) , the whole point of a hollowpoint is to create a greater braking effect so the pellet displaces more material by using the energy it has, hence the larger cores shown!

In your head you can get the idea it's heavier therefore hits harder but in reality its surface area (the actual area that transmits the energy) is the same as a lightweight pellet, and as its travelling slower its impact is less, but its momentum is greater, it's such a complex interaction that its very hard to grasp what's happening, but the cores give a visual example of the effect, bigger cores equal more physical trauma!

The trajectory comparison however is black and white , it's indisputable that a fast light pellet is less range critical than a heavy one, and in our 12ftlbs world the small differences in trauma come second to the ability to hit where you need to.

Shot placement is everything, we don't have the energy to rely on shock damage alone.

The reason Is actually getting to the bottom of what is real and asking the correct questions to get the right answers., I believe that the "terracotta wax question" so to speak is the incorrect question as the subject matter (massive intentional pun) isn't correct on so many levels. I asked you "how do you know" purposely, not to prove you are wrong but to acquire the foundations of the statement that you made. I actually want to know the truth of this situation and the source so I can go look and experientially learn it for myself, I couldn't give a monkeys who is right or wrong.
It's funny how people in this type of discussion always get mixed up between belief and hard facts, then they use YouTube videos of someone elses inconclusive experiment to create more weight to there belief.
I'm here, right now, offering an opportunity to see exactly what is going on here by carefully thinking about the questions to ask, or presenting a reasonable reason or angle as to why possibly that we shouldn't believe what the YouTube video shows because it is easy to "Imagen" (this is an important word here) what it might be like if you apply what you see to a rabbits head, in our own heads... Which is just plain wrong.
Please don't argue with me I'm not here to do that, I just want to learn as I'm sure do you, what is exactly right
Rhys

[airgunnut]

Around December 2009- April 2010 Airgun world did extensive testing regarding terminal ballistics, they looked at what happens to the shape of the pellet, they tested using jelly (they said it was closest to ballistics jell)
Every one seems to focus on the external ballistics (internal ballistics - what happens to the pellet in the barrel, external ballistics - pellet in flight, terminal ballistics - what happens when the pellet hits) if hunting you need a balance of power (foot pounds), accuracy and energy transfer.
Domed pellets, perfect for mid-long range but at 5-15m it's over kill (literately) so you need flat or hollow points, to be truly efficient, efective and safe you need to choose sutable pellets for each shot, as said in previous posts the pellet needs to transfer ALL it's energy to the live target, preferably with a head shot failing that a heart shot (you need to know there the heart is from every angle and if there is any bones/muscle that can stop the pellet before it hits the heart) an old shooter once told me that you shouldn't shoot an animal untill you have dissected one to see where all the internal bits are, so you know what is where, take a crow, (commonly thought of to be armor plated,) head is obscured, so a heart shot is needed, from the front there is large breast muscles and a large breast bone, both of these can stop/defect the pellet before it gets to the heart, side/profile shot, folded wings with bones, the multiple lares of feathers will absorb energy, back shot if you avoid the spine there is very little muscle to impead the pellet on the way to the heart.
Airgun pellets do produce hydrostatic shock, not that much, but it's there, the talk of wound tracks is pointless, there should be NO wound track as it should be head shots, with heart shots there should be very small wound tracks as you should know the best angle to avoid the energy sapping muscle and bone, some butchers ask for head shot rabbit only as they can get a premium price for un damaged rabbit meat (same goes for birds)

With pellets it's houses for courses, you have to know what your gun/pellet combo can/cannot do, having a 'good all rounder' pellet is not good enough, you have to have the best pellet for a perticuler job.

[MarkHolding]

If you use the Chairgun software, it has a range of pellets in its data base that you can put in at the various ranges, including your expected muzzle velocity. From this you will be able to click on the chart shot curve at the different ranges to see what the retained energy is. It's down to coefficient and weight of the pellet overall, but will give you a rough idea.

[krisko]

i have not got his raw data but he speaks about chrony work so to me it is experimental
here is more to read if you are interested in this
http://www.gatewaytoairguns.org/GTA/...?topic=14735.0

[Artfull-Bodger]

https://www.youtube.com/watch?v=3YrZqR-Ak0c&t=317s

guy tests BC in this video, over 12ftlbs though.

[Yafflle1234]

I think its also important to balance the need for penetration versus energy transferred to/retained in the target.

i.e A .177 at 15 yards passing straight through, for example, a squirrel thus unless a vital organ it hit the actual knockdown/damage potential is wasted as the pellet continues its flight. On the flipside and other end of the of the scale a .25 at the same range/target can also rely on the pellet remaining in the target thus the full energy is transferred into said target as well as the physical damage caused by a larger projectile.

[lensman57]

One thing that gets me with these tests is that terracotta wax just isn't flesh & bone... Just simply down to the fact you can mold it with your hands means it's very different. So I don't understand how this can be used as a reliable test substrate at all, it's bound to react differently to a pellet passing through than a rabbits head.

It's a bit like saying I'm going to test this rope strength using a different type of rope to the one I'm doing the test for !!!!??

I find such tests misleading even though they have been conducted in good faith. There was an on going one in AGW and although it didn't reveal anything we didn't know it also fell into the same trap of using clay. Clay is not fiberous like the skin and flesh of an animal so the deductions should be treated with a degree of caution. Using a 5 grs pellet to make a large hole in the clay does not mean the same will be happen to an animal nor using an ultra heavy pellet in a sub 12 ft.lbs air rifle. A pellet that is travelling at a pedestrian pace of 460 ft/s is hardly going to show its best at 20 yards.
For .177 at sub 12 ft.lbs any well desigend pellet between 7.9 grs and 10.5 will do the job. Either side of that and the bets are off.

A.G