.
This cartridge was designed by Bill Wilson of Wilson Combat and marketed in or around 2011.
The 7.62x40 WT, WT for Wilson Tactical, is a .223 Remington or 5.56 NATO case neck out to .308" or 30
caliber and shortened to 40mm so the cartridge will fit in an AR-15  (.223 Remington or 5.56 NATO) magazine.
It is is about 5mm longer then the 300 Blackout and 300 Whisper cartridges.     
Current Rifle Cartridges
7.62x40WT
t
.
Available for sale
produced by Wilson Combat
using new 5.56 Lake City
brass, H/S 2013 and
loaded with a 125 grain TNT
by Speer FMJ Projectile.
.
Note; see comparison photos, Left to right
5.56 NATO, 7.62x40WT
300 BlackOut