Help Me Understand

[thompal]

While looking at the Armscor web site, I came across this chart of their ammo:

Caliber

It appears that they make both .223 and 5.56mm ammo. Comparing the .223 and 5.56mm 55gr ammo, both have the same bullet weight, and the same BC. The 5.56 has a higher muzzle velocity, and chronos higher at 100 yards, but is slower than the .223 at 200 yards, and slightly slower at 300 yards.

Also, the energy figures shows the 5.56mm has more energy at 200 yards than the .223, and almost twice the energy than the .223 at 300 yards. If the 5.56mm 55gr bullet is going slower at 200 yards than the .223, shouldn't it have less energy?

I try to understand this stuff, but sometimes it just doesn't appear to make any sense to me.

 

[Ash]

Those calculations for the 5.56x45mm are incorrect.

Here is a calculator that I Googled.

Airhog: Muzzle Energy Calculations

 

[Aszerigan]

While looking at the Armscor web site, I came across this chart of their ammo:

Caliber

The ups and downs of this chart make no sense to me. They must have their data mixed up. I could see the higher velocity / muzzle energy from the 5.56mm, that's true. But as for the significant drop in Vel/ME compared to the .223 - that just can't be correct, especially considering the POI is nearly the same.