First of all, a .223 and a 5.56 are not the same, and this makes a huge difference on accuracy at distances. The is a popular misconception that the two cartridges are the same, that is not correct, the calibre is the same, but not the cartridge!
Please refer to my article on this subject that I previously wrote, it is available in my book Practical Gunsmithing for Beginners.
Accuracy at distance with a .223 depends on three things: –
First lets deal with twist rate.
Rifle barrels chambered for the .223 or 5.56 round come in a huge array of twist rates, from a 1:14 to a 1:6.5. There might be barrels out there with an even tighter twist rate than 1:6.5, this would probably be custom built barrels however.
As a rule of thumb, the lower the number of the twist rate the faster the spin.
Also, as a rule of thumb, 5.56 chambered rifles have a faster spin rate, and fire a heavier bullet than a standard .223.
However it is not as simple as this, some .223 chambered rifles have a twist rate of as low as 1:8, and can handle the heavier bullet, but this is the exception, and not the rule when buying a standard .223 rifle.
I have 2 .223 rifles that I shoot with, a Browning A Bolt target rifle with a twist rate of 1:9, and a Savage Stainless Steel with a twist rate of 1:12.
Secondly the bullet weight.
The faster the spin, the heavier the bullet! If you fire a 40g varmint round in a barrel with a twist rate of 1.7 the bullet will disintegrate, it cannot handle the forces imparted on it crated by the spin. Fast spin rates are used in 80g or 90g match bullets.
The wind.
Because the .223/5.56 bullet is so small and light the wind has a huge influence on the projectile. This, combined with bullet drop over distance has a huge influence on shooting accurately at long distances.
Ok, enough of the theory, how far can you accurately shoot with a .223/5.56?
All this being said, the wind has a huge influence on distance, you will not be able to achieve anything if the wind is blowing.
There are however some people out there that are taking the 5.56 out to 1000 yards or so, I will post a few videos of this below. I have no reason to doubt them, but these are serious shooters dedicating themselves to shooting long distance with small calibers!
Bullet drop on a .223 at 1000 yards is huge, they actually have to shim the front scope mount upwards on their scopes to compensate.
Why is the .223 adopted by the Military, and why is it such a devastating round?
First of all Weight!
The .223 is a lot lighter than the standard 7.62 round, so more can be carried! its as simple as that!
Secondly, its ability to yaw!
The .223 round had the ability to yaw, that is it will turn sideways when approaching transonic and sub sonic speeds, i will publish an article on this later. This makes it produce devastating wounds.
Tag der Veröffentlichung: 26.04.2016
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