I've posted this before, but now's a good time to do it again. I used the Barnes 300 gr semi-spitzers several years ago to shoot 3 deer. The starting velocity was 2173 fps. The 3 were shot at ranges from 10 feet to around 35 yds. The only one that expanded was the one that hit that 6-point buck from above at 10 feet. In that case it hit the backbone and the deer died pretty much instantly. In the second case, a doe at 35 yds, the bullet hit ribs going in and out and never expanded; she needed a mercy shot. The 3rd instance was another doe at about the same range. The bullet hit low near the liver and never expanded again. No bone was hit. Another mercy shot. I believe, without going over there, that Midway(Barnes) states that a velocity of 2400 fps is necessary for this bullet; and I can safely say that once it gets below the starting velocity of my load it's no longer reliable. Pity, it was the most accurate bullet I ever shot in the 45/70. The one guy I know who still uses that 300 gr, shoots a 460 Weatherby, and "downloads" the bullet to 2600 fps.