Convert Grains to Scruples
Convert Grains (gr) to Scruples (s ap) instantly and accurately.
Conversion Formula
s ap = gr × 0.05
About Grains
A grain (gr) is the smallest unit in both the avoirdupois and troy weight systems, equal to exactly 64.79891 milligrams. Originally defined as the mass of a single grain of barley or wheat from the middle of an ear, it has been a standard of weight since ancient times. Today, grains are used to weigh gunpowder charges and bullets (a standard .308 rifle bullet weighs 168 gr), pharmaceutical preparations in apothecary compounding, and the fineness of gold alloys. Arrowhead and fishing hook weights are also specified in grains.
About Scruples
A scruple (s ap) is a unit of the apothecary weight system equal to 20 grains or approximately 1.296 grams. Derived from the Latin 'scrupulus' (a small sharp stone used as a counterweight), it was the basic dispensing unit in pre-metric pharmacy across Europe. The apothecary system divided the fluid ounce into 8 drams, each dram into 3 scruples, and each scruple into 20 grains - a hierarchy memorised by every 19th-century pharmacist.
Quick Reference Table
| Grains (gr) | Scruples (s ap) |
|---|---|
| 1 gr | 0.05 s ap |
| 2 gr | 0.1 s ap |
| 5 gr | 0.25 s ap |
| 10 gr | 0.5 s ap |
| 25 gr | 1.25 s ap |
| 50 gr | 2.5 s ap |
| 100 gr | 5 s ap |