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How a Tranquilizer Dart Works in Slow Motion

Slow Mo Guys Explain How a Tranquillizer Dart Works in Slow Motion


Gavin Free and Daniel Gruchy, the Slow Mo Guys, are back with a new video. This edition of their popular YouTube channel uses slow motion to show how a tranquillizer dart works. The video captures the dart at 3,000 frames per second, and it still looks incredibly fast.

Over the course of 13 minutes, Free and Gruchy demonstrate how the dart, which is little more than a hypodermic needle with some fletching, works. The dart is typically a .50 calibre, and is propelled from the dart gun using compressed gas. The momentum of the dart transfers to a plunger when the dart hits the target, which then sends the drug out of the needle. Unlike other needles, the needle of the dart has a hole in the side rather than on the tip.

This configuration proves to be a boon to the Slow Mo Guys as it provides more dramatic footage of the fluid being discharged. In order to keep the fluid from escaping before it hits the target, a rubber sleeve is used to cover the hole. The dart has two chambers—one that contains the fluid and the other that is pressurized through a one-way valve. When the dart hits the animal, the rubber sleeve is pushed away, causing the pressure to push the fluid out of the dart.

How a Tranquilizer Dart Works

The video was shot using a Phantom Flex 4K camera to capture the flight of the dart at both 1000 frames per second and 3000 frames per second. Free and Gruchy have made a name for themselves in the online community thanks to their work capturing fast-moving events in slow motion. They have quite a following. Within just a week of posting the tranquillizer dart video, it had over 13 million views. They have quite a library of videos as well, so be prepared for a long day of binging—at least that won’t be done in super slow motion.