5.56MM
Cartridge, Caliber 5.56mm Ball, Carbine, Barrier
MK 318 MOD 0
DODIC: AB49
NSN: 1305-01-573-2229

and the

7.62MM
Cartridge, Caliber 7.62mm Ball, Rifle, Barrier
MK 319 MOD 0
DODIC: AB50
NSN: 1305-01-572-8492

Crane power point presentation.

Pictures of these 2 new rounds are on page 21 of 25 in the presentation.  Can someone explain to me how the front of a 62 grain OTM is supposed to be a Barrier defeater?  It looks like the center of the bullet is hollow or something.  These bullets where designed for the SCAR MK16's and MK17's.

Thank you.

Dupe: http://www.ar15.com/forums/topic.html?b=3&f=16&t=451073

Didn't read the rest of the post to notice that it's about a different topic.

Page 12 has some comparison gel shots of ATK TOTM/SOST style projectiles:  http://www.dtic.mil/ndia/2008Intl/Roberts.pdf

Some additional info here:  http://www.m4carbine.net/showthread.php?t=22379&page=2

Thank you very much, DocGKR.  Very helpful.