Correct
Those donāt REDUCE recoil as often colloquially described, but simply change the time frame in which the energy is transferredā¦ or a better way to explain is that it changes the recoil impulse
Other things such as muzzle breaks, and some compensators, do actually reduce recoil by venting gas in the direction of recoil impulse canceling some out
But something like a 12 gauge pump or a standard bolt action rifle doesnāt use these tricks to soften it, a 12 gauge recoil is still, but it doesnāt break your shoulder as people often love to over exaggerateā¦ at worst it bruises (typically from bad shooting form)
Back to the armor discussion,
armor is complicated
when looking at stuff like that helmet, the more important thing to look into is āback face deformationā
This is the effect of the armor catching and slowing down the bullet but it does it over a distance that is sometimes longer than the armor is thick, which results in forces being exerted into the body
In the case of a soft body armor (think cop vest)
It may stop the bullet but have something like 2ā of back face deformationā¦ so imagine instead of a bullet sized foot print on impacts itās a goofball sized impact that pushes into you 2-4ā at a good amount of velocity
Gunna hurt like a mother, possibly break ribs, or in the case of central thoracicā¦ it could stop or damage your heart depending on the shot
āStoppingā a bullet is only half the equation
You need to stop it quick enough without transferring too much blunt force impact to the wearer
Chinessium helmets often have very extreme levels of back face deformation, that would crack your skull or lead to severe TBI
Back face deformation, edge test, and shot density, and even special threat rounds are all things that complicate armor
NIJ is the standard go to org for certifications, but it costs money and many MANY companies skirt it by saying their product āmeets or exceedsā
(And only meeting or exceeding cherry picked parts)
or is ācompliantā rather than actually ācertified NIJ X standardā
Whatās even more fun and complicated is
Letās say you wanted to make armor that can stop .308 Winchester / 7.62x51 NATO
.223 Remington / 5.56x45 NATO is a smaller and lighter round, so youād THINK itās easier to stop that 308, but it depends on what type of armor we are talking aboutā¦
something like steel itās easier to stop 308 because itās a physically larger and slower bullet, regardless of energy
Where as the 223 will go thru it like a hot knife because of velocity and footprint
Those kind of Chinese companies will ātestā it with 308 and then let people make their own flawed conclusions that are everything lower is stopped by it
You also have things like poly plates, which uses I forget what, but a particular blend of plasticā¦ and works really wellā¦ until it gets coldā¦ and then itās properties changes
And ceramic plates if mistreated can develop internal hairline cracks that significantly weaken it
Fabric aramid soft armor can be significantly degraded from biological growth occurring inside it from humidity, so they are often sealed, but maybe that sealed bag is shitty and it allows in humidity from your body
Steel armor is often easily defeated by higher velocity rounds, and can cause such extreme spall from the shattered rounds to pose a lethal fragmentation risk
Anyone that says that body armor is easy, is either ignorant or lying
