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Felt recoil

Kinetic energy is part of it. The First Law of Thermodynamics says, "Energy cannot be created or destroyed", which means that the kinetic energy (force) of the bullet (from launch, not impact) is the same as the kinetic energy of the rifle.

edit: The recoil force isnt kinetic energy but rather Newton's second law, F = m*a or, for every action, there is an equal and opposite reaction. So the mass of the bullet times its acceleration equals the mass of the rifle times its acceleration.
 
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In the case of a shoulder fired rocket launcher the rocket's exhaust is not contained within the weapon. If you do not believe that the weight of the projectile is involved, shoot something like a 45=70 with a heavy bullet and compare it to a rifle of the same weight with a lighter bullet, the same weight of ejecta and velocity. Bottom line, your example and theory are incorrect. Certainly muzzle brakes work but comparing the recoil of the same rifle with extremes of bullet wight will also demonstrate my point.
In your scenario, there are inconsistencies that make the scenarios incomparable.

Shooting a light bullet and a heavy bullet in a different rifle to the same velocity is not a comparison, for a number of reasons, mainly because you may not get complete burn in both cases using the same quantity of the same powder.

This is not about the bullet, it's about the powder, and to properly compare, the bullet and rifle must be the same too.

You need the same weight bullet to the same velocity, with different powders, and to compare the felt recoil, it has to be the same rifle as well.

Changing rifles introduces unnecessary variables. Some rifles have terrible ergonomics, and enhance felt recoil. The 45-70 Marlin, for example, is the worst for felt recoil. It's too light, there is too much comb drop, and the stock is too thin. The .416 Alaskan from Ruger has incredible ergonomics and is very comfortable to shoot. You can shoot a box of factory ammo in one session and walk away smiling.

Shoot a .416 Ruger Alaskan with a 400 grain bullet at 2300 fps. The felt recoil will be less than from a Marlin 45-70 shooting 400 grains at 1600 fps.

Take the 45-70, load it with 400 grain bullets, one round medium burning powder, one round slow, load the same velocity, and you will feel a big difference, a difference that is far out of proportion to the increase in powder weight.
 
Felt recoil has a lot to do with gun fit and technique.... I learned how important proper form and a good technique is when I started shooting skeet with a 12ga all day long... When I first started it beat me up pretty good until a friend told me your technique is crap... After a learning curve I can shoot literally all day now without even redness.... I also have a terrible rotator cuff and it's helped from killing it also... If the guns in the wrong spot it will lead to pain....
 
Stock design is a major factor in felt recoil. A friend has a couple of 7mm rifles of similar weight. One is a Remington 7mm Express, that is painful to shoot, and the other, a Weatherby in 7mm Weatherby magnum, is comfortable. I feel confident that virtually all actual ballisticians would disagree with you on this, but as long as you are happy, there is no problem.....for you.
 
Kinetic energy is part of it. The First Law of Thermodynamics says, "Energy cannot be created or destroyed", which means that the kinetic energy (force) of the bullet (from launch, not impact) is the same as the kinetic energy of the rifle.
No propulsion force from expelled gas ?

Energy is perfectly conserved.

The powder and primer compound are converted to gas. The gas has energy because it expels the bullet from the barrel. The energy from the gas translates to bullet velocity. More energetic powder, more gas, more velocity, until there is too much powder for it to burn in the barrel, then the velocity stabilises.

Does a railgun have recoil ? I mean an electromagnetic railgun, not a rifle.
 
Felt recoil has a lot to do with gun fit and technique.... I learned how important proper form and a good technique is when I started shooting skeet with a 12ga all day long... When I first started it beat me up pretty good until a friend told me your technique is crap... After a learning curve I can shoot literally all day now without even redness.... I also have a terrible rotator cuff and it's helped from killing it also... If the guns in the wrong spot it will lead to pain....
Fred Wenig certainly taught me a lesson.

 
No propulsion force from expelled gas ?

Energy is perfectly conserved.

The powder and primer compound are converted to gas. The gas has energy because it expels the bullet from the barrel. The energy from the gas translates to bullet velocity. More energetic powder, more gas, more velocity, until there is too much powder for it to burn in the barrel, then the velocity stabilises.

Does a railgun have recoil ? I mean an electromagnetic railgun, not a rifle.
I think that everyone's point is that it is not one or the other. It is both. Look up the formula for computing recoil. You will see that the weight of the ejecta and the bullet as well as velocity are part of it.
For that matter, take your pick.
 
JBM Ballistics is a ballistics authority, and I use their calculator exclusively for my drop charts.

What I don't see in any recoil equation is the energy content of the powder, the gas pressure and the diameter of the exit nozzle, which translate into the rearward propulsive force on the rifle. And I need to see that to rely on an equation for recoil.
 
Since the question is about "feeling" recoil, the argument will never stop.

It all boils down to time under pressure, what happens in the barrel, is transferred to the shoulder and is a product of burn rate and efficiency. This changes with not only bullet weight, but also bearing surface.

Next is muzzle pressure. Which also can be manipulated through burn rate.

I tested this fairly thoroughly for a backyard scientist, to the point of using the same rifle and bullet using powders of differing burn rates that would achieve the same velocity, with the same charge weight.

This eliminated all variables except what is not used as an input from most "recoil calculators"

Results were judged by a few factors, feeling, ease or ability to return to target, and with an AR rifle, vertical dispersion on a double tap at 200 yards, with and without a suppressor.

I found Qucikload to have the most convenient recoil calculator for this work, as it used the exact loads to calculate recoil.
Some of the better online recoil calculators will factor in charge weight, but have no way to calculate the weight of unburned powder that needs to be added to bullet weight on exit from the muzzle.

For me, Higher peak pressure, lower muzzle pressure, was more controllable. Faster returns to target, less vertical dispersion on a double tap. Measurable results.

Testing was done with many rifles, loads and configurations, A traditional 8 pound 45-70 with a crescent buttplate, AR 15 subsonic suppressed and a lot in between.

What was felt, depended greatly on stock design and shooting platform. Off hand different than field bipod, different than bags and a rest.

Sometimes the feeling matched the models, sometimes it didn't.

Just observations.
 
Hey thanks for posting I have been looking for the guy that has that pretty stock wood.... I saw it in an advertisement awhile back but couldn't find it again.... Man he has some beautiful stocks....
Fred ran the Fajen business before it shut its doors. He went about 40 miles north of Warsaw, to Lincoln, and started his own business. I am not sure if Fred is still alive or not.
 
I found Qucikload to have the most convenient recoil calculator for this work, as it used the exact loads to calculate recoil.
These calculators already calculate recoil energy, they just translate if for us as muzzle energy.

They use the volume of the cartridge, the weight of the powder, the volume of the barrel, the energy of the powder - all the parameters that define the amount of energy produced by the powder - they calculate how fast the bullet is going to be - and they give you muzzle energy.

Muzzle energy is the energy of the recoil.
 
These calculators already calculate recoil energy, they just translate if for us as muzzle energy.

They use the volume of the cartridge, the weight of the powder, the volume of the barrel, the energy of the powder - all the parameters that define the amount of energy produced by the powder - they calculate how fast the bullet is going to be - and they give you muzzle energy.

Muzzle energy is the energy of the recoil.
The rifle starts moving long before the bullet exits and it is that running start or lack of, that changes the feel and the actual force of the muzzle energy.

Changes the rate of acceleration at bullet exit.
 
Stock design is a major factor in felt recoil. A friend has a couple of 7mm rifles of similar weight. One is a Remington 7mm Express, that is painful to shoot, and the other, a Weatherby in 7mm Weatherby magnum, is comfortable. I feel confident that virtually all actual ballisticians would disagree with you on this, but as long as you are happy, there is no problem.....for you.
Yes, lots of factors in stock design and perceived recoil. One is the comb shape. That Weatherby cheek piece slopes down as it goes forward. Under recoil, the gun comes up and back. A straight comb climbs into your cheek, where the downward slope of that big Weatherby raised cheek piece slopes away from you. A man(or woman) can take a good bit more pounding on their shoulder than in the face...perception!
 
I have found that high pressure loads produce more felt recoil, other factors being the same.
A .416 rem with a 400gr at 2400 fps is sharper than a .416 Rigby with the same bullet at an identical velocity in the same rifle. I noticed it in CZ. Same rifle, stock, weight and the .416 rem was more unpleasant to shoot. Very sharp as opposed to more of a push.
 
I have found that high pressure loads produce more felt recoil, other factors being the same.
A .416 rem with a 400gr at 2400 fps is sharper than a .416 Rigby with the same bullet at an identical velocity in the same rifle. I noticed it in CZ. Same rifle, stock, weight and the .416 rem was more unpleasant to shoot. Very sharp as opposed to more of a push.
The Remington case capacity is 104 grains of water and the Rigby is 129 grains of water, they are not the same case and the Rigby has a smaller expansion ration. Meaning the Remington gets more energy out of less powder.
 
Fred ran the Fajen business before it shut its doors. He went about 40 miles north of Warsaw, to Lincoln, and started his own business. I am not sure if Fred is still alive or not.
Yeah, Benton County MO seems to be the walnut capital of the country. Bishop was located there as well.
A couple years back a group I am involved with, Missouri Disabled Sportsman got a Red Ryder bb gun with a custom Wenig stock to auction for a fundraiser. It was pretty impressive, there are some pics in this old thread. https://www.missouriwhitetails.com/...enefiting-missouri-disabled-sportsmen.230311/
 
The Remington case capacity is 104 grains of water and the Rigby is 129 grains of water, they are not the same case and the Rigby has a smaller expansion ration. Meaning the Remington gets more energy out of less powder.
The rem runs at much higher pressure. The rigby is loafing along at 2400 at a low pressure
 
Yeah, Benton County MO seems to be the walnut capital of the country. Bishop was located there as well.
A couple years back a group I am involved with, Missouri Disabled Sportsman got a Red Ryder bb gun with a custom Wenig stock to auction for a fundraiser. It was pretty impressive, there are some pics in this old thread. https://www.missouriwhitetails.com/...enefiting-missouri-disabled-sportsmen.230311/
I am sure that if Wenig had something to do with it, it was top notch.
It would be nice, but not necessary to see it. I would have to log into a new website to see it and I don't do Facebook
 
I think that everyone's point is that it is not one or the other. It is both. Look up the formula for computing recoil. You will see that the weight of the ejecta and the bullet as well as velocity are part of it.
For that matter, take your pick.
I’ve used this calculator before and found it to be extremely accurate in how it translates to felt recoil. It is a great indicator.
Dave
 

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