I enjoyed the show about restoring the M18 Hellcat. But as it got into the topic of the M18's ammunition, I groaned in disbelief.
The M18 used HVAP as its special ammunition. This is high velocity armor piercing. The show implied that it used hollow charge ammunition (like a bazooka). It had no such ammunition.
The HVAP basically had a small tungsten core inside the projectile that was surrounded by a lighter metal. This allowed great velocity and also great penetration into armor.
The sherman tank (with the long 76mm gun) could fire this same ammunition but I believe that the hellcat had priority over it. More than likely, TD units traded this ammo for goodies from teh Sherman 76mm guys.
