No .38-40 Win factory load we have sourced carries 1,000 ft·lb for mule deer past the muzzle. Here is why, load by load.
| Load | gr | Max ethical yd | MV fps | 500 yd ft·lb | Shoulder shot |
|---|---|---|---|---|---|
| Winchester Super-X 180 gr Power-Point | 180 | not enough | 1,160 | 198 | behind the shoulder only |
Deer-class rules of thumb; a slightly bigger animal than a whitetail. Legal: CO: 1,000 ft·lb at 100 yd. Floor used: 1,000 ft·lb at impact plus the bullet's published expansion velocity. Orange = a target or varmint bullet (construction, not energy); red = never carries the energy. Sources: chuckhawks.com, www.petersenshunting.com.