Jim Elbrecht wrote:
>
> gregz > wrote:
>
> >First thing I saw in the army, the m16 exploded a watermelon vs large bore
> >slow shot, just made hole.
>
> I'll have to call BS on that. I've seen a few folks shot by various
> weapons and the M-16 is the one I'd most like [least dislike?] to be
> shot by. [especially with military ammo]

It's physics. Energy is 1/2 mv^2 while momentum is mv.
An increase in v (velocity) has a much greater effect
on energy than does an increase in m (mass). But, they
both have the same effect on momentum. So, for the same
amount of energy from the same amount of gunpowder, the
v^2 term means the small fast bullet has much less mass
than the big slow bullet, so it has much less momentum
even though it has the same energy.

A small bullet with lots of energy but little momentum
will readily give up that energy on impact, resulting
in an impact that resembles an explosion. A big slow
bullet with the same amount of energy and lots of
momentum will tend to punch through the target and
keep going.