My hardcast WFN weighs 420 gr., and I have no experience with 325-400's. However, the performance of the 420 should certainly be very similar to a 400 WFN. Before I began to use the 400 XTP almost exclusively in my .475's, I took several head of game with the WFN, including large hogs, bear, and buffalo. Penetration was full on all animals but one, but I run my loads faster than your inquiry...between 1150-1350 fps, depending upon the gun, to flatten the trajectory a bit.
The one animal on which penetration was not complete is instructive. On a wild water buffalo in Argentina, a frontal chest shot penetrated diagonally the entire length of the body to the hip bone, where it turned and traveled half way down the leg to the knee joint...a total of 7 feet of penetration, on approximately 2000 lbs. of buff. The muzzle velocity of that load was 1350 fps, the hit was at about 75 yds. or a bit less. I expect a 400 WFN @ 1000 fps will penetrate a bit less, but the experience of several people seems to show it will be perfectly adequate, penetration wise, for most commonly hunted game. A WFN can hit like a hammer.
