Review of the new round from RifleShooter.com:

Enter the 7.62x40WT.  Based off the 7.62x40mm wildcat, the 7.62x40WT is based off 5.56x45mm parent case trimmed to 1.560″ and then re-sized to accept 30-caliber bullets.  With factory offering from 110-125 grains, this cartridge seems to be the perfect hunting upgrade for the AR enthusiast.  The only part of a 7.62x40WT rifle that is different from a standard .223 AR is the barrel.  That’s it.

7.62x40WT Project Site