How many grains are in one dram?

Exactly 27.34375 grains make one avoirdupois dram. This comes from the avoirdupois system: 7,000 grains per pound, 256 drams per pound, so 7,000 / 256 = 27.34375.

Why is the ratio not a whole number?

The grain and dram were standardized at different times for different purposes. The grain (1/7,000 of a pound) and the dram (1/256 of a pound) have a ratio that produces a fractional number. The avoirdupois system was not designed for mathematical elegance.

Which unit is more useful today?

The grain is far more useful. It remains the standard unit for bullet weights and powder charges in ammunition manufacturing worldwide. The dram is essentially obsolete.

Grains to Drams (gr to dr) Converter

1 gr = 0.0366 dr

1 Grain equals 0.0366 Drams (1 gr = 0.0366 dr). Convert Grains to Drams with formula, table, and examples.

One grain equals exactly 1/27.34375 drams, or approximately 0.03657 drams. Both units belong to the avoirdupois system, with exactly 27.34375 grains per dram. The grain (the smallest avoirdupois unit) and the dram (the next step up) were both used in English trade, but the grain outlived the dram by finding an irreplaceable role in ammunition manufacturing.

How to Convert Grains to Drams

dr = gr × 0.0365714286

Multiply the value in Grains by 0.0365714286

Take your value in Grains
Multiply by 0.0365714286
Read the result in Drams

Common Grains to Drams Conversions

Grains (gr)	Drams (dr)	Status
1 gr	0.036571 dr
5 gr	0.182857 dr
10 gr	0.365714 dr
15 gr	0.548571 dr
20 gr	0.731429 dr
27.34 gr	0.999863 dr
50 gr	1.828571 dr
100 gr	3.657143 dr
200 gr	7.314286 dr
437.5 gr	16 dr
480 gr	17.554286 dr
500 gr	18.285714 dr
1,000 gr	36.571429 dr
5,000 gr	182.857143 dr
7,000 gr	256 dr

Good to Know About Grains to Drams Conversion

The avoirdupois system's survival depends almost entirely on the grain. The dram is obsolete, the ounce competes with grams, and the pound competes with kilograms. But the grain has no metric competitor at its scale - 64.8 milligrams is an awkward number in metric, while it is a clean 1 in grains. As long as the shooting sports industry uses grains, the avoirdupois system's smallest unit will continue to justify the system's existence.

Grains to Drams: What You Need to Know

A 5-grain aspirin tablet is about 0.183 drams. A 150-grain rifle bullet is about 5.49 drams. Before metrication, a pharmacist might have dispensed both medicines and measured both in grains and drams, using the same balance for healing and (indirectly) for harming. Today, the grain serves ballistics while the dram has largely retired.

What is a Grain? gr

A grain is a unit of mass equal to exactly 64.79891 milligrams. It is the same in the avoirdupois, troy, and apothecaries' systems, derived from the 1959 international agreement defining the pound as exactly 0.45359237 kilograms.

Imperial Troy Apothecaries ammunition weight bullet measurement historical pharmacy

Learn more about Grain →

What is a Dram? dr

A dram (avoirdupois) is a unit of mass equal to 1/16 of an ounce or 1/256 of a pound (1.7718451953125 grams). Historically used in pharmacy and old cooking recipes.

Imperial historical pharmacy old recipes whisky measurement

Learn more about Dram →

Going the other way? Use our Drams to Grains converter.

Grains to Drams FAQ

Exactly 27.34375 grains make one avoirdupois dram. This comes from the avoirdupois system: 7,000 grains per pound, 256 drams per pound, so 7,000 / 256 = 27.34375.
The grain and dram were standardized at different times for different purposes. The grain (1/7,000 of a pound) and the dram (1/256 of a pound) have a ratio that produces a fractional number. The avoirdupois system was not designed for mathematical elegance.
The grain is far more useful. It remains the standard unit for bullet weights and powder charges in ammunition manufacturing worldwide. The dram is essentially obsolete.

Non-Frequently Asked Questions About Grains to Drams

Questions nobody should ask - but someone did.

The grain found a niche that no other unit could fill: ammunition. Bullet weights of 55 to 300 grains produce manageable whole numbers. In drams, those same bullets weigh 2.01 to 10.97 drams - less tidy numbers. Grains also work well for powder charges of 15 to 60 grains. The grain's scale was perfectly matched to ammunition; the dram's was not matched to anything that survived.
Almost certainly not. Even dedicated handloaders, who know grain weights by heart, never need to convert to drams. They go from grains directly to grams if metric is needed. The 27.34375 factor is a mathematical artifact of a system designed long before anyone planned to connect its sub-units across levels.
Nothing would improve. A 168-grain match bullet becoming '6.14 drams' offers no advantage. Powder charges of '42.5 grains' becoming '1.554 drams' adds an unnecessary decimal. The grain provides cleaner numbers at the scale ammunition operates. Sometimes the smallest unit in a system is the most useful - the grain proves this.