Comment on Anon takes up microdosing

• sp3ctr4l@lemmy.dbzer0.com ⁨1⁩ ⁨day⁩ ago

  Ok, you are apparently just a moron.

  Again… the dude in the original post states that psrt of his original plan was to work his way up to a .223.

  If you missed that part of the original image, please go look at and read it again.

  Here, let me highlight it for you, as you struggle with reading comprehension:

  Image

  I have no idea why you keep insisting I am making some kind of strawman or non sequitor argument by just explaining what would happen if he just went to carrying out that part of his plan.

  …

  A .22 pellet air gun round carries about 5 to 15 ft-lbs of energy leaving the barrel.

  A .22 short bullet from a firearm carries about 80 +/- 30 ft-lbs of energy leaving the barrel, though this will vary by the exact round and barrel length.

  A .22 lr bullet carries 130 to 200 ft-lbs of energy, though this will vary by the exact round and barrel length.

  A .223 bullet carries about 950 to 1350 ft-lbs of energy though this will vary by the exact round and barrel length.

  …

  Human skin, on the other hand, just has a hard limit of how many psi it can resist before breaking, about 100.

  A callous may add maybe up to 10 to that number, but this is negligible with any firearm cartridge at point blank range.

  Because all calibers mentioned in the OP image are either the same or very close to each other, the ft-lbs of energy is being applied to human skin/flesh over a very close to the same amount of surface area, so you don’t really need to take into account the potentially variable surface area to get a psi figure, and can instead just use ft-lbs as a decently accurate comparative measure of destructiveness.

  The .22 refers to the diameter of the pellet/round, in inches, plug that in with the area of a circle formula (A = pi * (d/2)^2) and with a bit of rounding for simplicity, you get about 0.038 square inches.

  Because this idiot is shooting himself point blank, the projectile travel distance is negligible, so you end up with Energy of Projectile / Area of Impact.

  Because I am doing this in Imperial instead of Metric, lets just say all these .22 projectiles are roughly .22 in^3 volume… now you can do:

  (ft-lbs of projectile energy / 12) / 0.038 in^3

  ~= impact psi

  Because the two other numbers here are constant and do not change for everything from a .22 pellet up to a .223 cartridge… we can just say that:

  ft-lbs * 2.2 ~= psi.

  As you can see, the max of 15 ft-lbs from a pellet turns into 33 psi, under the skin breakage threshold.

  Every single bullet the OP mentions, on the other hand, exceeds to vastly exceeds the max skin breakage threshold of 110 psi…

  .22 short is about 180 psi

  .22 lr is about 350 psi

  .223 is about 2600 psi

  … This is all middle school physics and math, apparently you either haven’t yet taken those classes or did not do well in them.

  …

  All of these rounds, and the pellet, are capable of being stopped by a certain number of sheets of paper, at certain ranges.

  Even at literally 0 distance from the barrel of a gun, if you put enough phone books in front of an AR15 and fire a round, a certain number of phone books will stop a .223 round.

  You can easily see this yourself without even leaving your seat:

  There are many videos of such tests on youtube, ‘how many X will it take to stop Y cartridge?’ is a fairly popular video format… phone books often feature in such videos, as they are relatively cheap.

  source

  • hobovision@lemm.ee ⁨1⁩ ⁨day⁩ ago

    Sorry bud, it sounds like you think I believe someone could train their body to become bullet proof. That’s not what I’m saying.

    I’m saying your argument is fallacious. Your conclusion is correct, but your argument fails.

    Also, you can’t just convert impact energy to pressure like that. I’m not familiar with the equation you’re using (is it just energy divided by the volume of a 0.22" sphere?), but I do know that impact is much more complex than that. It’s going to depend on both the bullet and the impact surface. Bullet geometry and material will change things, for example hollow points vs full metal jacket. Then there’s the impact surface, it’s hardness, strength, ductility, even viscoplasticity (materials can deform in different ways at the really high strain rates you get in an impact event). Think about the way Kevlar armor works. It dissapates some of the energy by stretching and breaking the strands of Kevlar and it reduces the impact force on a body by spreading it over a larger area and slowing the bullet over a longer distance. The person wearing the Kevlar armor still gets much of that energy delivered to their body.

    source

    • sp3ctr4l@lemmy.dbzer0.com ⁨1⁩ ⁨day⁩ ago

      You don’t get it.

      Again and again I tell you this and you do not listen:

      I was not in my original comment making an argument as to the mechanics of why real world skin resistance to bullets does not follow video game logic.

      I was providing an example of what would happen if this idiot had shot himself with a .223, which he said he planned on doing.

      An example… and an argument… are not the same thing.

      I literally do not know how to explain this to you in other words.

      …

      As to my more recent breakdown:

      You can in fact do a reasonably accurate approximation of the actual forces and figures involved in the way I just did.

      Terminal ballistics wound theoreticians did similar, if not exactly the rough model I just gave you for about 70 years untill computers allowed for more complex materials modelling…

      … and untill ballistics gelatin tests with high speed cameras became a popular way of assessing total maximum wound cavity volume, speed of expansion of the wound cavity volume, end result wound cavity volume, shape and size of wound cavity, tendency of a bullet to tumble or break apart or expand, velocities/ranges at which commonly struck bones result in a bullet that stick into a bone vs bounce off of it vs shatter it and now the bone fragments themselves cause wound cavities etc etc.

      …

      .22 in^3 of volume is a reasonable approximation of the volume of the projectile because while yes, the actual rounds are rounded, lenghtened, conical forms, not perfect spheres… doing all the math to account for the exact volume of each round would take a lot more time, and would barely change the end result of the actual volume you end up with.

      The impact surface is constant in this scenario (human skin), so … no need to worry about that as a variable.

      Nobody makes .22 hollow points or jhps or armor piercing rounds, nor does anyone make those for .22 airgun pellets. Those only exist for 5.56/.223, but again, the point of this is more recent approximation of mine is to just illustrate the relative magnitude of energy involved between the 4 rounds the OP mentions… because that on its own is sufficient to demonstrate the point.

      …

      Human skin breaks at about 100 PSI, pellet guns do not output over that threshold, all firearms do output over that threshold at point blank range, shooting yourself or otherwise doing something to your skin does not increase that PSI breakage point number in any meaningful way.

      That right there is all you need to show the folly of the ‘theory’ of gaining bullet resistance via repeated ‘exposure.’

      …

      You don’t need an astoundingly precise model here, a middle school level model is sufficient to illustrate the point, I am not designing bullets.

      Ductility, viscoplasticity, hardness, kevlar, deformation speed and patterns… none of this needs to be considered: the scenario is a dumbass shooting himself at point blank range into his own totally exposed leg.

      A third of your comment here is about how kevlar works… yep thats neat, I might have gone into that if this guy was shooting himself to test his own homemade kevlar armor… but he isn’t, so it isn’t relevant.

      …

      The scenario we are dealing with here is constrained by the context of the post.

      Sure, modelling impact effects for all bullets, with all kinds of targets and armors… at different ranges… sure, yep, a full, universal model of bullet wounding effects is quite complicated.

      But that’s not what we are talking about here, we are talking about a specific scenario with only a few variables.

      We are not designing the ballistics damage model of a MilSim like Arma Reforger or Gray Zone, we are mocking an idiot on 4chan, sitting in his computer chair, shooting himself in the leg.

      Even if we were designing a milsim quality ballistics model, let me tell you: I have actually done that in my spare time a few times, and what you quickly realize is that a whole lot of very complex calculations can be massively simplified, and you end up with 99.99% accuracy fidelity model in 99.99% of scenarios that actually occur in gameplay, for an underlying model that runs 10x faster and thus has less network and physics calc lag, so now you can support more players or npcs, larger levels.

      So many of these ‘be 100% accurate to real life’ calculations to include all kinds of realworld effects… end up having a very, very negligable effect on that end result of ‘how much should this damage the player’… but they add massive computational overhead to your game.

      source