7.62 / 6.5 / 5.56 vs concrete block

[stanc]

i was thinking the m855 with the steel penetrator core would have penetrated through all the jugs. I guess not.

As Bill noted, bullet construction of M855 is relatively fragile, with a much thinner jacket than larger calibers.

Also, for tough barriers like this, there's no substitute for mass. Even though the 7.62 and 6.5 MatchKings lack the steel tip of M855, their post-barrier effects were far greater.