why does recoil increase exponentially more with bullet weight than with velocity when kinetic energy is much more dependent on velocity than weight?
shouldnt a pissing hot .22-250 50gr plinker recoil way more than a much slower .308 180gr bullet according to physix?
Fuck ya mudda
Conservation of momentum
so recoil is basically inertia?
Yes, in simple terms, recoil can be described as the backward movement of a firearm after it has been fired due to the principle of inertia. When a bullet is fired from a firearm, the firearm experiences an equal and opposite force in the opposite direction. This force causes the firearm to move backward, or recoil, in the opposite direction of the bullet. The mass of the firearm, combined with the force of the bullet, determines the amount of recoil that is felt by the shooter. The principle of inertia states that an object at rest tends to stay at rest, and an object in motion tends to stay in motion unless acted upon by an external force. In the case of a firearm, the external force is the explosion of the gunpowder, which propels the bullet forward, and the recoil is the result of the equal and opposite reaction of that force.
to add it's not just the bullet but also the escaping powder that's moving forward, causing equal and opposite reaction moving rearward, aka the gun recoils. That's why muzzle brakes are effective - they redirect the gasses sideways so they don't accelerate the gun backwards, with most average rifle rounds cutting recoil about in half. The heavier gun also has less velocity for the same momentum and it's slower to decelerate against your shoulder so the felt recoil is less sharp and more pleasant.
can you explain why a suppressor reduces recoil? its not redirecting gasses but rather accumulating them in the baffles at the muzzle
so shouldnt suppressors technically increase recoil?
While a suppressor does not directly reduce recoil, it can affect how the recoil is perceived by the shooter by altering the weight, length, and muzzle blast of the firearm similar to a compensator.
It's the exact same as a muzzle brake. Think about it.
Suppressors siphon off muzzle gasses and trap them in the baffles. It achieves the same effect
hes a witch! burn him at the stake!
the mass of the gasses is negligible
hence also the momentum, hence also the recoil that is caused by them
explained, the suppressors effect on recoil is due to increased mass of the gun and the change in the moment of inertia
A much lighter muzzle break significantly reduces recoil by redirecting the gases. The same effect occurs in a suppressor
The recoil reduction in a muzzle brake is related to the fact that it spits the gases out sideways and not forwards. A suppressor still has all gas leave the front of the barrel. Unless it's an atypical suppressor design that vents gas out the sides, it isn't operating on the same principal as the muzzle brake. Perhaps there's some contribution from letting the gas cool down a bit before it exits where some kinetic energy gets converted to heat.
>The recoil reduction in a muzzle brake is related to the fact that it spits the gases out sideways and not forwards
The exact same thing happens in a suppressor. Gases expand into the baffles, directing some of their momentum outwards, instead of forwards.
But at no point are they able to leave the suppressor but forward.
There is a reduced momentum of gas going forward out of the suppressor due to gas expanding into the baffles. Gases which get caught in the baffles lose momentum buy colliding with the solid pieces of the suppressor itself, so even when they do eventually escape through the end of the suppressor, they no longer have sufficient momentum to significantly effect recoil. Gas expansion directed outwards is what reduces recoil in both devices.
The idea is that a suppressor slows the gasses down so much that you don't feel the recoil from them as they vent out, I believe. Same momentum transfer spread across an X times longer period of time will produce an X times smaller kick
Moment of inertia increases, leading to less muzzle rise and the weight of the gun increases, leading to less recoil.
Suppressors are designed to slow down the escaping gasses of the firearm. The gasses don't have a lot of mass but they do have a lot of velocity, which is a big part of their effect on recoil. If you slow down the gasses enough their effect on recoil will be greatly reduced, resulting to a similar effect to a muzzle brake. Some muzzle brakes are more effective than suppressors as they can not just redirect the gasses sideways but also backwards a little bit when they have angled baffles, however these are less popular as they're mich less pleasant to shoot with, even compared to the other muzzle brakes.
>mass of bullet*velocity+propellant mass*gas exit velocity
would a suppressor also reduce recoil by reducing gas exit velocity?
It's largely inertia as you think likely of inertia. "Heavy and fast is hard to stop."
Actual inertia however is simply the ability to resist a change of velocity, ie straight up just mass. (This is simply what Newton's second law, "acceleration = Force / mass", tells us.) It has nothing whatsoever to do with the objects velocity. Though we can still explain why heavy bullets tend to produce more recoil with "proper" inertia: Heavy bullets have more inertia, so to we need to push harder on them to get them going. As we subject the bullet to a greater force we also greater reaction force (aka recoil) in accordance to Newton's third law.
The recoil of a firearm is primarily determined by the conservation of momentum, which states that the momentum of the gun and bullet before firing must be equal to the momentum of the gun and bullet after firing. When a bullet is fired, it gains momentum in the direction opposite to the direction of the bullet's motion. In order to conserve momentum, the gun must also experience an equal and opposite force in the direction opposite to the bullet's motion, which is perceived as recoil.
The recoil of a firearm is not directly related to its kinetic energy, but rather to the momentum of the bullet and the gun. While kinetic energy is dependent on both velocity and mass, momentum is solely dependent on mass and velocity. Therefore, the recoil of a firearm is more dependent on the mass of the bullet than its velocity.
In general, as the mass of the bullet increases, the momentum of the bullet and the recoil of the gun will increase. The velocity of the bullet also affects the momentum of the bullet, but to a lesser extent than the mass of the bullet. This is why a heavier bullet will typically generate more recoil than a lighter bullet, even if the lighter bullet is traveling at a higher velocity.
So, in answer to your question, a .308 180gr bullet will generally produce more recoil than a .22-250 50gr bullet, even though the latter has a higher velocity, because the .308 bullet is much heavier and thus has a higher momentum.
>While kinetic energy is dependent on both velocity and mass, momentum is solely dependent on mass and velocity.
That makes absolutely no sense
It doesn't. In kinematics, momentum is always conserved. Momentum is directly equal to the mass in motion times it's velocity.
That is total recoil (mass of bullet*velocity+propellant mass*gas exit velocity)
Then you divide that by the gun's mass to get the recoil velocity (if you have a muzzle brake or suppressor, some of the recoil velocity is negated by that).
But remember kids
>momentum is conserved.
Because recoil equals momentum, not energy.
This is a rather classical blunder (though more commonly encountered when people talk about terminal ballistics). Energy and force is all you remember from high school physics, possibly all you were taught. So when you then try to understand things about motion one or both of those will have to cover everything. This is helped along by you most likely not really having understood either in the first place, so you don't immediately notice when your explanation demands that they work in ways they don't.
The biggest missing piece of the puzzle for you, one that's often even more important than the energy, is momentum. Calculate it by simply taking mass times velocity, meaning it's less velocity-dependent than the kinetic energy (and so relatively speaking more dependent on the mass). Contrary to kinetic energy (but just like velocity and force) momentum is directional. Much like the total energy, the total momentum is always preserved, but whereas we can get rid of kinetic energy by turning it into other forms of energy momentum cannot be changed into anything else. Taken together its directional nature and that we can never make it just go away is why we can't really get rid of recoil, ever, we can simply at best make it affect something other than the shooter either by bolting down the gun or by letting the recoil blow a bunch of gasses or digestive biscuits or something backwards as the projectile gets pushed forwards.
Running the math. Let's take a 180 grain .308 running off at 700 m/s. That'll give you a bit over 2800 J of energy. 1 ounce shotgun slug (438 grain) at 445 m/s gives us much the same. But for the momentum that has to go through your body and down into the ground? 8.12 kgm/s for the .308, but 12.6 kgm/s for the slug.
kinetic energy = 1/2 * m * v^2
momentum = m*v
conservation of momentum means that the backward momentum of the gun, aka recoil, must equal the forward momentum of the bullet (+the gasses, but assume those are negligible)
on the flipside, the kinetic energy of the bullet scales proportionately to its mass, but quadratically to its velocity
so, you can get a lot more kinetic energy for equal recoil by using a smaller, faster bullet
>so, you can get a lot more kinetic energy for equal recoil by using a smaller, faster bullet
Doesn't that basically render anything above .223 caliber obsolete?
If I can kill everything from crows or groundhog with 53gr V-Maxs to joggers with M193 to elk and moose with 77gr TMKs with the most marginal recoil possible, of what use are obsolescent fudd calibers like .30-06 or .300 fuddmag with their dog shit twist rates and moron sucker punch tier recoils?
Larger bullets have a better surface area:volume ratio, which allows them to better handle drag and crosswinds just by virtue of having proportionally less exposure to those forces. Also, there is a theoretical upper limit to how fast gunpowder can push projectiles, and even if you aren't approaching that limit the further away you are from it the more efficacious the gunpowder is at accelerating your projectile.
So there is no point, but "da loooooooong range"? What difference does any of that make when 77gr .223 TMKs have a BC of 0.467 compared to like a .308 155gr 0.462 BC?
Why should I take 5 times the recoil for identical BC? Why should I take 5 times the recoil when 77gr TMKs do this to elk at 287 yards?
You shouldn't. Think about it like this: two curves on a graph where BC efficiency tends to become easier with larger bullets while effects slope in the opposite direction with higher velocity.
Modern VLD/ELD bullets in the 2600fps range are the ez mode of cartridge design. They might not be best (I personally would prefer a 4.8mm ~35gr at 4800 fps. The limit of smokeless is about 6000fps.) but they're a simple retard-proof sweet spot for casual target shooters who also go hunting every other year.
So why are muh big slow boolits even a thing still? They obviously perform worse ballistically and energetically. Why does this fuddardation persist? Why did the military abandon 5.56 in favour of a nu308 (when old308) was abandoned for all the reasons that make a light and fast bullet so based in the first place?
there are a lot of tradeoffs in play
smaller bullet -> more kinetic energy for equal recoil
larger bullet -> less effect from crosswinds
faster bullet -> more drag
larger bullet -> smaller surface area, less drag per unit of mass
and ofc, assuming equal kinetic energy, larger bullet -> more dmg to the target
this is what is known as a multiobjective optimization problem
you have several things you like and you'd like to maximize, several more you don't like and would like to minimize, and the variables under your control connect all of them, making it impossible to maximize all the desirable effects and minimize all the undesirable effects at the same time
its not really solvable in the sense that its possible to find a single optimum for all situations
and all of that is before you consider practical issues like gun price/availability, bullet price/availability, etc
simply put, its all about tradeoffs
in practice, if i may offer some advice for dumbfucks, stick to 9mm.
its cheap, its available, its big enough to cause lots of dmg at distances that are likely to matter for you
maybe also consider .357 if you're into revolvers
if you're the sort of person who can hit things >> 1000yrds, you aren't here asking for advice.
Uhh 150gr makes more boom than 50gr
And a suppressor stops the gasses from spewing out the barrel like a rocket and pushing you back. Some of the energy is converted into pulling the gun forward/redirected sideways instead of directly opposite you
cube square law. the sad reason we will never get Mecha
Would you rather take a big wide shit or a flaming hot diarrhea shit in one long string? Basically it's like that.
P = mv
Ke = .5mv^2
Notice how speed only linearly increases momentum but squared in kinetic energy.