Impact force?

[Carbonrocket]

This is not a .177 vs .22 debate it is a hopefully scientific question.

 

Please I dont want any of the which is best for vermin just a defined answer to this question.

 

If two rifles .177 and .22 shoot together at the same target say 35m. They are both 11.8 foot pounds.

 

The .177 will have give the pellet a greater speed than the .22 but...

The .22 having a greater mass will it be less affected by the drag and carry its mass to the target.

 

 

Will they hit the 35m target with the same force?

 

Not .177 vs .22 more do they hit with the same force.

 

Thats all

 

Carbon

[Doggone]

.22 will have more wack, but hit the target lower

Andy

[Carbonrocket]

See thats the question.

 

I always use .22 but would like a definitive answer to.

 

IS THE INPUT EQUAL TO THE OUTPUT.

 

I am after a math answer to this question.

 

Not interested in how both a .177 or .22 can kill vermin but what are the impact powers!

 

Carbon

[airssassin]

Here is my attempt at an answer...

 

They both hit the target with exactly the same force once you discount how well a pellet retains energy. Actually a .22 will carry its energy a little further due to it's increased mass. When they hit the target, the .177 has less frontal area and less mass and therefore doesn't transfer it's energy in the same way.

 

Two interesting factors which I have heard about on different sites. 1) the size of the "wound channel" with .22 and 2) a .22 pellet is more likely to knock your quarry out before it dies of the actual trauma. This is what people refer to as "knock down" power and it is purely due to the weight, frontal area and energy transfer.

 

That said, I shoot .177 because I prefer the way it behaves and if you hit the kill zone it makes no difference what calibre you use.

[smsguitarist]

Scientifically yes .22 has more forward travelling energy, but due to its size it will slow down faster upon impact due to more material surface area (bone/muscle) preventing it from travelling further. This is why .177 pentrates more. A .177 will encounter less resistance and in turn penetrate further.

 

So to answer your question using mathematics:

 

A 16grain .22 pellet leaving the muzzle at 11.5ft.lbs will reach a target at 35 yards with 8.722 ft.lbs

 

A 8grain .177 pellet leaving the muzzle at 11.5ft.lbs will each a target at 35 yards with 7.064 ft.lbs

 

So with these results it comes down to what you prefer. Do you prefer a heavier pellet with more 'knock down' (knock out) or a pellet which requires more precise shooting but penetrates more?

 

I hope this has been a sort of answer you are looking for.

 

Take care,

Lewis

[Thumpersniper]

im also quite interested in a math answer to this having recently started using a .177 a bit and liking the faster zippy pellet, always used a .22 before though. There must be a calculation sort of kinetic energy or whatever it is!

 

someone on here told me 177 for feather 22 for fur, so perhaps 177 is more penerative while 22 is after more of a trauma wound.

 

On this note should i apply for a fac air rifle or a .22 rimfire? is there a huge difference in energy between these? and do the police take a slightly lighter (probably not the word as it is a serious matter) approach to a FAC air rifle request, with good reason being needing more range to deal with vermin, but not wanting to damage meat with the 12 bore? only used air rifle and shotgun before but too many rabbits i would like a more powerful rifle to get more range.

 

SP

[Thumpersniper]

Does anyone take anything other than head shots with air rifles? if not presumably if a pellet enters the brain the animal will be killed imediatley reguardless of the pellet size so 177 would be more effective (according to the sums) although evryone seems to think theres not much difference!

[SteveT]

Hi,

 

As for the impact at 35 metres with a .177 and .22. Yes the muzzle exit can be of equal force, but theoretically, due to to the difference in speed and weight (around 200feet per second) the .177 should maintain more muzzle energy due to its smaller size, and better aerodynamics.

 

The .22 will lose power at a greater speed than a .177 hence the excessive difference in trajectory. At 50 yards you are talking 2 inch drop with a .177, with a .22 you could be talking anything upto 12 inches drop. To me, this would say the maintained muzzle energy at point of impact is greater with a .177 than with a .22.

 

I could be wrong....But hey, i'm no scientist

[Axe]

Hi,

 

As for the impact at 35 metres with a .177 and .22. Yes the muzzle exit can be of equal force, but theoretically, due to to the difference in speed and weight (around 200feet per second) the .177 should maintain more muzzle energy due to its smaller size, and better aerodynamics.

 

The .22 will lose power at a greater speed than a .177 hence the excessive difference in trajectory. At 50 yards you are talking 2 inch drop with a .177, with a .22 you could be talking anything upto 12 inches drop. To me, this would say the maintained muzzle energy at point of impact is greater with a .177 than with a .22.

 

I could be wrong....But hey, i'm no scientist

 

 

You have all that some what back to front, i'm afraid.

 

This assumes that both rifles are setup the same, scope height 1.5" both have muzzle energy close to 11.8ft/lb and zeroed at 30yards firing Crossman Accupels.

 

The .177 will have retained 80% of its momentum as opposed to the 85% of the .22 @ 35yards.

Ft/Lb at the same distance is 7.6 for the .177 and 8.4 for the .22.

Velocity for the .177 is 80% and the .22 84.5%.

 

These are approximate figures taken from chair gun.

 

With the same setup the drop at 50 yards from POI for the .177 is -2.6 inches and -5 inches for the .22.