5 of 6 .303 British factory loads carry 1,000 ft·lb and expansion velocity for mule deer; the best reach 400 yd (Federal 150 gr Power-Shok JSP). Ranked, with the drop chart for each.
| Load | gr | Max ethical yd | MV fps | 500 yd ft·lb | Shoulder shot |
|---|---|---|---|---|---|
| Federal 150 gr Power-Shok JSP | 150 | 400 | 2,690 | 826 | behind the shoulder only |
| Hornady Custom 150 gr SP InterLock | 150 | 400 | 2,685 | 835 | behind the shoulder only |
| Winchester 180 gr Power-Point | 180 | 400 | 2,460 | 835 | behind the shoulder only |
| Federal 180 gr Power-Shok JSP | 180 | 350 | 2,460 | 727 | behind the shoulder only |
| Remington 180 gr Core-Lokt Soft Point | 180 | 250 | 2,460 | 506 | behind the shoulder only |
| Remington UMC Centerfire Rifle 174 gr Full Metal Jacket | 174 | wrong bullet | 2,475 | 678 | 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.