Quote:
Originally Posted by Timmyy
To think I was actually buying into you knowing a lot about guns and stuff. You really sounded knowledgeable but then you post this.
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If it's in reference to the calibers and their capacity here ya go
If it's about the calibers I had mentioned.
Shooters room to victims on the ground ranges 400 to 500 yards.
55gr 223 at 400 yards 1500/1600ft per second carrying with it 315-295ftlbs of energy.
55gr 223 at 500 yards 1300/1400ft per second carrying with it 220-200ftlbs of energy.
308 projectile weighs vary from 145gr to 220gr
Common weight of projectile ranges 147-155gr
Go with 150gr to keep it simple.
150gr at 400 yards traveling at 1900/2050ft per second carrying with it 1200-1300ftlbs of energy.
150gr at 500 yards traveling at 1800/1900ft per second carrying with it 1000-1100ftlbs of energy.
It's basic physics. Go to a macro scale. What will go through a 2 foot thick concrete wall?
A smart car doing 50mph (55gr 223)
A half ton pickup doing 70mph (150gr 308)
223 drops close to pistol velocity at those ranges, and the lighter grain projectile loses energy to where, yes it is lethal, but entering a body, it's not exiting.
308 on the other hand, can.
The variables to velocity are
1. Barrel length
2. Projectile weight in grains
3. Air density temperature+humidity and barometric pressure
4. Cartridge charge in grains and burn rate of powder
5. Barrel twist rate. If the twist rate is too fast or too slow the projectile will destabilize and instead of fly like a football tossed by a quarter back, it will tumble like a football that has been kicked, which is known as "key hole"
The variables to energy
1. Velocity
2. Projectile weight
3. Projectile density and construction. (Hollow points are designed to expand and dump most of its energy upon impact)
Density being the projectile jacket copper typically unless you buy that Ukraine or Russian bi-metallic crap, or copper washed TMJ Plus the projectiles core density. Lead and antimony mixture. There's soft and hard cast projectiles. Which is why you don't run soft cast bullets in a Glock due to its rifling. You will get heavy lead deposits in the barrel increasing pressure and potentially have it explode in your hand.
For example you could have a 55gr 223 projectile that has a soft core or dense core Copper FMJ or Bi-metallic FMJ.
Some indoor ranges
do not allow bi metallic jacketed rounds as they will damage the backstop or have a potential to ricochet or cause a spark. Have a spark with unburnt gun powder you may have a bad day...
That tula/wolf bargain steel case bi-metallic stuff, the jackets deform but tend to stay together, shoot into a sand bag at 50 to 100 yards, the jacket deforms but tends to stay together some of the core may eject out of the base, and the base of the projectile will look like you squeezed it with a pair of pliers.
Copper jacket, the jacket tends to shed/fragment peel off especially if it has a cannelure, and the core will either fragment or remain together depending on density.
Softer core=fragment "Harder" core=less fragment stay together.
TMJ copper plated projectile target rounds usually deform and fragment with or without cannelure.
Density of the human body varies bone, tissue, muscle. It will deform the projectile as well as slow it down and stop it. Ballistic gel density was developed to mimic the density of a body to test a projectiles ballistics. Expansion (hollow point), deformation, fragmentation (jacket and core), and penetration depth.
An FBI standard and calibrated block of ballistics gel at 400 and 500 yards shot by 223 and 308 will reveal the 223 will more than likely penetrate and stop. 308 may pass through. It carries more velocity and carries more energy.
It's physics Timmyy...