His trebuchet launched a 4 gram projectile at 776 miles per hour.

That's obviously extremely lightweight for trebuchet payload, but for comparison, his projectile is approximately 62 grains so approximately twice as heavy as 30 grain high speed 22LR rounds. And approximately 1.5 times as heavy as 40 grain subsonic rounds.

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drcongo 14 minutes ago | parent | next [-]

What does grains mean in this context?

	▲	jihadjihad 10 minutes ago \| parent \| next [-]
		It’s a super old unit of measurement for mass [0], idea being that a “grain” is a single seed of wheat etc. 1 gram is a little over 15 grains, and there are 7000 grains per (avoirdupois) pound. 0: https://en.wikipedia.org/wiki/Grain_(unit)
	▲	bjackman 10 minutes ago \| parent \| prev [-]
		It's a unit of mass used in the firearms world

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an hour ago | parent | prev [-]

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