There has been long running debate over which is the most effective
round and what our ground troops should be using, 5.56mm x 45, or 6.8mm x
43 SPC.
Well, for me, that’s a no brainer – 6.8mm of course.
Why? Because of its terminal effects! In layman’s terms terminal
ballistics is how the projectile reacts and what damage it causes when
it strikes the target.
But don’t let me influence you in any way with my opinion; I’d like
you to put your reasons forward as to which round you think is more
suited for our troops.
5.56mm and 6.8mm Rounds: The Facts
There are many ballistic charts that you can view on the web, most
showing that velocity is reasonably similar between the 5.56mm and 6.8mm
rounds. Compare a 77gr 5.56mm projectile against the 115gr 6.8 and it
is very close indeed, however kinetic energy is anywhere from 40-50%
greater at shorter ranges, and up to 35% out to 600 yards.
The 6.8 SPC round has the same energy at 250 yards as the M855 has at
the muzzle. At 600 yards it has the same energy as a 7.62mm M43 at 275
yards, M193 at 250 yards and M855 at 375 yards. Since the 6.8mm is of a
larger calibre and greater sectional density than the 5.56mm, it will
use this energy more effectively when producing terminal damage.
Performance can be increased slightly by using 110gr ammunition, giving
you more velocity and less bullet drop over range.
The lower velocity of the 115gr ammunition combined with more kinetic
energy makes this round less susceptible to deflection from soft cover
such as foliage, shooting through glass (in the case of vehicle
interdictions) and chest rigs.
6.8mm upper receivers will fit AR lowers, but you will need to change
the bolt though and use specific 6.8 mags. I have fired 6.8 SPC
ammunition from 5.56mm magazines but the heat that was generated
expanded the mags – causing stoppages. The tolerances inside the mag are
quite tight because the 6.8 cartridge is bigger in diameter. Although
the calibre is larger, the difference in recoil is hardly evident and is
quite controllable when engaged in rapid fire.
Ok, 6.8 will significantly increase your chances of neutralization or
incapacitation with a first round strike. It goes without saying that
different types of projectiles will produce different results, and that
shot placement is still the key no matter what type of round is used.
However, we can’t always achieve this, so the introduction of a large
caliber that fills the gap between 5.56mm and 7.62mm is vital for the
safety of our troops and is necessary in our fight against terrorism.
My guess is that money is the overriding problem. But perhaps it
would work out cheaper to supply something that will do the job more
efficiently without wasting ammunition…or lives!!