Retained energy - .22 vs .177

[Muskett]

The larger calibre only delivers if it hits the vital organ. Accuracy important? Accuracy is everything.

I've had a squirrel take x5 .22 pellets and then jump for my face from the tree. All because of poor shot placement. The .22 alone wasn't enough and all pellets were found the far side under the skin. It was dead but didn't know it.
It used to be normal practice to heart shoot rabbits with a .22. Problem was the rabbits had enough time before expiring to get to their burrows.
A .22 can feather plug. Generally pigeon flies 200m and then keels out of the sky. Seen it, been there.
I do like the .22 on rats though but at least distance is never great.

Modern air rifle vermin shooting asks for precision kills, not the solid hits of old. If you can do it with a .22 then you are a better shot than I; a good few people are. Certainly John Darling could make the .22 work for him though I'm unsure he always used a 12ft/lbs rifle??
Your call, for me its .177.

[Artfull-Bodger]

If you make a perfect brain shot, or a perfect under the wing pit on pigeon shot, then what pellet is irrelevant at normal ranges. No pellet shape will make any difference to the outcome of poor shot placement. A .177 is marketably easier to get perfect shot placement due to its higher velocity over a .22. A .22 certainly sounds to give more wallop but if it doesn't hit the mark it won't do the job.

So, use the most accurate and consistent pellet in your rifle, and make that one good shot of it.

It really is as simple as that.
Anything more is the fun of testing, just like testing the rest of your kit. Its part of the fun of the hobby and the results are fun too. The more confident and familiar with your kit the better you will be.

Totally agree, shot placement is the critical factor, it is fun to mess about with this stuff and it dispels a lot of the myths that tend to spring up, so worth doing anyway, but yeah it's all for the fun of it.

[Black Beard]

Assume a pellet is just scaled up from .177 to .22
Mass is proportional to cal^3
Drag is proportional to frontal area * velocity ^2
Frontal area is proportional to cal^2
Velocity for a 12ftlb rifle is proportional to cal ^-3/2
So Drag is proportional to cal^2 * (cal^-3/2)^2
Or Drag is proportional to 1/cal
Energy lost is Drag * distance travelled
So the .177 loses energy 24% faster than a .22 initially.

BB

[harvey_s]

Don't agree on penetration however, the smaller area of the .177 has always penetrated better in every test I have done due to the simple formula of force over area?

I understand the theory and agree it makes sense, but I can only tell you what happened in practice on a tin plate - other materials will react differently...and there are fur/feather sayings that I suspect have some truth in them to support this.
But not being a particularly enthusiastic hunter I'm probably not the one to present a reasoned argument either way on the subject.

[rhyslightnin]

I'm expressing my experiences messing with this kind of thing not arguing , this is a discussion.

You see I'm a complete geek who spends more time testing things than actually shooting!

I spent ages a number of years ago experimenting with different materials to see if hollowpoints worked, if pointed pellets worked etc
I tried plasticine, lard at different temperatures, gelatine (strawberry jelly), putty, clays, in the end I got a small box of ballistic gel off a guy on the net!

What did I learn ,

12ftlbs is not enough to properly deform a hollowpoint pellet unless the material was extremely dense, quite hard clay in my experiments.

that the results were mirrored no matter what the material I used, the more dense, the less the physical effect, and less dense the greater the effect but all behaved the same relative to each other, except the Ballistic gel which was great for testing penetration but without a high speed camera didn't give any other info.

what was clear was velocity was paramount, and the reason is simple if you take ten different pellets of the same calibre and look at them end on they are all the same area, and that's what the target is struck by, the frontal area, the different profiles flat, hollow, pointed etc varied the physical effect but the main criteria was speed!

I used a different measuring principle to the guy in the video , I used a syringe and measured the cc's of water each hole held , but the results the guy in the video has found is pretty much the same as what I did.

Rabbits heads are not made of terracotta wax, nor jelly or lard, but the results were the same relative to each pellet no matter what the material, and that's going to be the same for a rabbits head, (sorry to be a stickler here but it is still a guess (maybe very educated but still a guess) without actually testing on rabbits heads we cannot say for sure, it is effectively saying "what it might be like..")their skulls are paper thin and their brains similar to gel, so yes you can use a similar material to get a picture of what does what.

As I said I'm not arguing I'm expressing my findings, I have tested this I suggest shooters try it to actually understand the principles, the problem is its a very long process and you have to have a very controlled system in place to eliminate errors.

Or in my case making a right old mess in the garage.

Thanks for sharing your experience and the expements that you have conducted.
My experience as I say is only in the field just what I have found from shooting rabbits, pigeons, squirrels & corvids.
Now I really only just started getting problems with runners when I started using a .177 which I never experienced with a .22 particularly with pigeons. I changed to a heavier pellet which seems a bit better but still not as good. Now, my testing isn't exaustive but I intend to really look at this as soon as I have collected and set up my new PCP which is a .22 I will be taking both of them into the field and testing them.
It's such a subjective thing & I guess the only thing to do is find what works best in the end regardless of caliber or pellet type.
Thanks artful bodger, IL let you know how I get on with my testing.
Will you be going to the bash at T20's?
It would be good to put a name to the face and chat more about this

Atb
Rhys

[lensman57]

In the case of a live target what may also be considered is the lethal shock radius. I now a .22 does have a much larger radius but whether it is really that much more than a .177 at these sub 12 limits needs to be investigated.
I honsetly wish that the .22 had a none FAC limit of 17 ft.lbs. It would have made a lot of difference to the accuracy within the short air rifle ranges without being " particulary dangerous " as defined by law.

A.G

[krisko]

i agree, they should change it for both .177 and .22,


.177 wants to run around 900, that is clearly a fact by manufacturers now. That would yield 18fpe with 10grain pellet, for simplicity 18fpe for both .22 and .177.
.22 wants to run at around 30fpe in the US they all do that.

this is to keep up with advances in airgun technology. i would not mind to be registered or a small admin fee.
on one side the authorities say it is not humane to use airguns on the other side they dont allow you to use more power.

hunting pellets like polymag or barracuda extreme or the hollow point would expand better, enlarging the crossection. practically a .22 will expand to size of a .25 or more. a .177 will pop to a size of a .22

[Artfull-Bodger]

In the case of a live target what may also be considered is the lethal shock radius. I now a .22 does have a much larger radius but whether it is really that much more than a .177 at these sub 12 limits needs to be investigated.
I honsetly wish that the .22 had a none FAC limit of 17 ft.lbs. It would have made a lot of difference to the accuracy within the short air rifle ranges without being " particulary dangerous " as defined by law.

A.G

Your right on the money here, the problem IS the lack of energy, the inability to fire the projectile at a higher speed,

If for instance you fire a 10.3 gr pellet at 700fps into your test medium you will get particular sized hole (the shock radius, the distance the material is displaced) and it takes a percentage of it's energy with it as it penetrates through.

Now fire the same pellet at 900fps and you get a much larger hole yet the pellet takes even more of it's energy with it, it's the same pellet but the impact speed is the defining factor for the size of the cavity.

So because we cant use the 900fps, as it would be over 12ftlbs, all we can do is use a lighter pellet to create a greater shock radius or cavity whilst limiting the amount of energy wasted by over penetration.

But this simply does not matter unless you put your shot in the right place, and that's where the lighter faster pellet is more forgiving.

[krisko]

in the US they used to define lethal at around 60-80fpe. usually they count the number of boards the projectile can penetrate.

well we know superman
:-)

but there is more common sense there. you cant deny that..

[Artfull-Bodger]

Thanks for sharing your experience and the expements that you have conducted.
My experience as I say is only in the field just what I have found from shooting rabbits, pigeons, squirrels & corvids.
Now I really only just started getting problems with runners when I started using a .177 which I never experienced with a .22 particularly with pigeons. I changed to a heavier pellet which seems a bit better but still not as good. Now, my testing isn't exaustive but I intend to really look at this as soon as I have collected and set up my new PCP which is a .22 I will be taking both of them into the field and testing them.
It's such a subjective thing & I guess the only thing to do is find what works best in the end regardless of caliber or pellet type.
Thanks artful bodger, IL let you know how I get on with my testing.
Will you be going to the bash at T20's?
It would be good to put a name to the face and chat more about this

Atb
Rhys

I'm a postman and work Saturdays so I simply don't get the time to go as my one day off a week (Sunday) tends to be already filled.

I always used .22 for vermin control, and used hobbies out to 35yds which was my self imposed limit as this was the furthest they would reliably group , I did try hollow points but they never grouped well in any of my barrels so stuck to hobbies as they could be fired at up to 680fps and flew much flatter than the other .22 pellets I tried, I did try .177 but despite finding it easier still to get the headshots I wanted I lacked confidence in it after a squirrel in a tree took a hit from behind his jaw which exited just above his eye on the opposite side and was not dead, having made this shot with hobbies which dropped them like a brick, I switched back, the shot wasn't perfect, and it's impossible to be perfect all the time as they can move just as you shoot, the .177 was just too small to do the required damage.

[TORNADOS7]

Well all I gotta say is '.22/Superdomes' shot close to the legal limit produce some spectacular results...

[GPConway]

To answer the original poster's question ...

...
Can anyone point me in the direction of hard facts about the retained energy of .22 in say 16gns and .177 in 10gns (I prefer JSB Heavies) so I can see if there's any advantage in moving back to .22 to offset the more challenging trajectory?

Newton reckoned that:
KE = ½ M*V² = W * V²/(2 * 7000 * g) Ft.Lbf
Where KE = Kinetic Energy (Ft.Lbf)
W = projectile weight (Grain)
V = instantaneous velocity (Ft/s)
g = standard acceleration due to gravity = ~32.174049 Ft/s²

For any given projectile, KE is proportional to V² (W and g remaining constant) and its Ballistic Coefficient is a measure of its ability to retain velocity.
So, if two similarly-shaped projectiles are launched with the same initial KE, then at any particular range the projectile with the higher BC value will retain more of its initial velocity and consequently more of its initial KE.
As a bonus, the projectile with the higher BC value suffers less wind drift too.
Eg.,
Pellet #1: 0.177 JSB Exact Heavy, 10.3 Grain, BC(GA) 0.026, MV = 709 Ft/s
KE @ Muzzle = 11.5 Ft.Lbf, KE @ 50 Yards = 7.0 Ft.Lbf (61.2%), Windage @ 50 Yards = 4.97" (10 MPH c/w)
Pellet #2: 0.22 JSB Exact Heavy, 16.0 Grain, BC(GA) 0.033, MV = 571 Ft/s
KE @ Muzzle = 11.5 Ft.Lbf, KE @ 50 Yards = 7.9 Ft.Lbf (68.4%), Windage @ 50 Yards = 4.67" (10 MPH c/w)

Nothing much in it in practical terms. However (and IMHO only), given the alleged greater difficulty in precise shot placement using the 0.22 and considering only the two JSB pellets specified, the 0.177 would seem to be the better bet.

George

[krisko]

relatively new video about airgun pellets

https://www.youtube.com/watch?v=7IjK26Giaic

[TonyL]

Quite enjoyed that video; thanks for posting.

Quite a bit of it not really relevant at sub-12, but still good nonetheless. And further cementing much of the information that Jim Tyler has provided in AGW and from people like BallisticBoy and many other knowledgeable people, re BC and sectional density.

And, as always, reaffirming that accuracy always has to be the most important consideration.

[Hellequin]

Really interesting thread this one, especially for me at the minute as I've just sold my only .177 rifle with the rest all being .22 cal.

To be honest I like both and have had success (pest control/hunting) with both over the years, in fact up until about 2009 I'd used .22 air rifles pretty much exclusively on live quarry. As others have said, at 12fpe accuracy really is all and that means learning the drop of each set up and getting good at range estimation and/or buying an LRF...

Personally speaking I don't think I'll miss having a .177 for a while, it just means that I don't have to do so much brain recalibration when I take out a different rifle, and I'll probably drop fewer pellets too!