Can a small arms bullet knock you off your feet?
Discussion
Guy testing a bullet proof vest dosen't seem to move much.
http://www.youtube.com/watch?v=wUqUrR8L1Zo
http://www.youtube.com/watch?v=wUqUrR8L1Zo
Use Psychology said:
isn't there a difference between not falling over when you know someone is going to push you, and not falling over when you're not expecting it? This is why people don't fall over when they fire guns - they are braced and expecting the recoil.
And if the round goes straight through it is not imparting all its energy. In a way, the faster the bullet, the less likely the victim is to fall due to inertia.Bag of sugar on table, knitting needle. Push it slowly - it falls over. Stab it and it stays put. The faster you stab it the less it moves.
But the projectiles hitting people don't impart all their energy into the movement of the person either.
There will be heat, particles breaking up, forces transmitted in other directions etc. The actual KE that gets put into a person is probably pretty tiny. If the kick of the weapon is about the same as a punch to the held out palm (like boxers training do), then the victim is going to feel a smaller equivalent of that as the bullet is pointy and takes much more time to slow down, and has slowed down before even getting to the victim.
So no, no bullet will knock you OFF your feet. I guess you get to a point where you could, but you'd need it to be slow enough not to go into/through you, which means it needs to have a lot of mass to get lots of KE, which means it is really big too. A big heavy bowling ball at 75mph may get you knocked off your feet?!
Hmmmm
Dave
There will be heat, particles breaking up, forces transmitted in other directions etc. The actual KE that gets put into a person is probably pretty tiny. If the kick of the weapon is about the same as a punch to the held out palm (like boxers training do), then the victim is going to feel a smaller equivalent of that as the bullet is pointy and takes much more time to slow down, and has slowed down before even getting to the victim.
So no, no bullet will knock you OFF your feet. I guess you get to a point where you could, but you'd need it to be slow enough not to go into/through you, which means it needs to have a lot of mass to get lots of KE, which means it is really big too. A big heavy bowling ball at 75mph may get you knocked off your feet?!
Hmmmm
Dave
An old biking mate of mine was in the forces and was on duty in NI. He was hit in the stomach and it floored him. No idea on the size or the gun, but it was from a distance away so I guess it was a rifle. He was a stocky guy about 5ft 9. He likened it to being punched in the stomach, and was on his back, winded...andthe rest is a blur.
Chilli said:
An old biking mate of mine was in the forces and was on duty in NI. He was hit in the stomach and it floored him. No idea on the size or the gun, but it was from a distance away so I guess it was a rifle. He was a stocky guy about 5ft 9. He likened it to being punched in the stomach, and was on his back, winded...andthe rest is a blur.
I've shot lots of animals that are smaller than people with guns from 308, 22, 22 rim-fire, shotguns with fine shot through to BB, and most animals just drop when hit.Nothing goes flying backwards.
A rabbit shot with a 308 just nigh on explodes, and they are soft-tipped hunting rounds not military FMJ. They don't go flying backwards several metres. Nor do foxes, they just fall over where they were stood with a big squishy hole where the bullet went in.
Even watching a bull being shot in the head with a 22 250 soft tipped ammo, something a bit more 'massive' and upon impact it's head just dropped to the floor, no kick back as the bullet hit the skull, no look of any energy of significant amount going into it's body, nothing.
Shoot a 22 250 through 1/8in steel I section girder end about 2kg weight tops, propped up on some hard soil, soft tipped ammo again, girder stays stood up with a hole clean through it.
A solid FMJ is going to be even more likely to keep going and NOT put KE into the thing it hits, and soft-tipped heavy ammo like 308 still tends to zip straight through most organic stuff!
Hmmmmmm
Dave
On the ranges with 7.62m NATO rounds from SLRs and GPMGs the targets were mounted on 4 inch thick wooden frames. When I was in the 'butts' the wooden frames wouldn't even vibrate when the bullets hit them, holes would just appear as if by magic. No energy was imparted to the 4 inch wooden planks at all. Not sure what that adds to the argument but it was fascinating to watch, especially when they were tracer rounds. Sometimes they would hit a bullet that was already buried in the sand and then they would bounce anywhere, which made things fun.
As several posters above have mentioned in a round about way it is a case of having sufficient energy to force the subject over and at the same time dissipating the required amount of energy 'into' said subject. Even something as heavy duty as a .500 S&W (as an example) the impact energy, though probably adequate, will not be absorbed - it'll exit and the energy will be 'wasted'.
.223 Rem using 50grn. ballistic tips(dum-dum) at 100 yards & 3000fps will not knock over pigeon. It won't cause it to 'explode' either (insufficient body mass). The round enters and exits. Though said pigeon won't get up.
What we need is something with low velocity and high muzzle energy. Say a large caliber BP propelled cannon ball?
.223 Rem using 50grn. ballistic tips(dum-dum) at 100 yards & 3000fps will not knock over pigeon. It won't cause it to 'explode' either (insufficient body mass). The round enters and exits. Though said pigeon won't get up.
What we need is something with low velocity and high muzzle energy. Say a large caliber BP propelled cannon ball?
from experience a .22 subsonic rimfire round to the ribs at 10ft feels like a hard punch but leaves a s
t load more brusing, certainly didn't "move" me. How much energy is required to knock over say a 75kg person? and if you a wearing body armour what percentage of the bullet energy will be absorbed by the wearer?
t load more brusing, certainly didn't "move" me. How much energy is required to knock over say a 75kg person? and if you a wearing body armour what percentage of the bullet energy will be absorbed by the wearer?
Chilli said:
Mr Whippy, where did I Say that anyone went flying backwards?! I've been punched in the stomach, ended up on my back, but never went flying, backwards, through the air!
Have you ever shot a bloke in the stomach? Infect, have you ever been shot in the stomach?!
You didn't say anyone went flying backwards anywhere, but I was just adding that for clarity generally as this thread is about being knocked off your feet and I was giving lots of examples of soft-ammo that just cuts straight through metal to organic without knocking things over or even giving them a good punch of impulse.Have you ever shot a bloke in the stomach? Infect, have you ever been shot in the stomach?!
I doubt you get the impulse of being punched in the stomach, but the resulting pain might feel like you were hit in the stomach.
To be fair, if you are shot then your recollection is probably going to be blurred.
I've been shot in the head with a 22 air rifle at about 25 yards. It bloody hurt. I didn't feel it like a punch to the head, or even a tap to the head... just a sudden excruciating pain and lots of running around holding my head
Dave
scrwright said:
from experience a .22 subsonic rimfire round to the ribs at 10ft feels like a hard punch but leaves a st load more brusing, certainly didn't "move" me. How much energy is required to knock over say a 75kg person? and if you a wearing body armour what percentage of the bullet energy will be absorbed by the wearer?
Really!? So you were wearing body armour?t load more brusing, certainly didn't "move" me. How much energy is required to knock over say a 75kg person? and if you a wearing body armour what percentage of the bullet energy will be absorbed by the wearer?.22 40grn. Sub @ 1000fps will penetrate at that distance. You sure you don't mean an air rifle or was the beer talking?
Ayahuasca said:
or a lead ball from a Brown Bess?
The BB 1" ball does a reputation for limb removal more than body penetration like modern rounds. The American civil war was the last large scale 'war' that used low velocity non-cartridge BP driven large cal bullets. The majority of deaths on the battlefield were not directly from bullet impact and internal trauma but the habit of this heavy high energy but low velocity rounds to detach limbs and for the combatant to then die of large scale blood loss on the battlefield.
Edited by Marlin45 on Wednesday 15th August 13:24
nope, lucky for me it was a short round (650fps-ish?), went through my barbour and got hung up in a fleese under it. 12" bruise & broke the skin (could of been a crack to the rib). Luck it hit my ribs in the side of my back, a bit lower & it would have been in my kidney. A good advert for not leaving a rifle about during summer holidays when bored 15yo kids (me & mate) can find it. Was impressed the bullet had the pattern of the barbour cotton impressed into it
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