Here’s a fun little detail that’s so easy to miss that barely anyone has noticed in more than a decade: the sniper in Team Fortress 2 has a common battlefield injury known as a “Garand Thumb.”

This detail was pointed out in the TF2 subreddit by user anevar a full 13 years after the game came out.

The injury, for those who took a look at the above photo and still weren’t able to figure out what I’m talking about, is a dark bruise underneath the fingernail. There’s a chance you’ve suffered a similar bruise yourself after smashing your finger in a door or hit it with a hammer. For soldiers, video game assassins, and WWII gun enthusiasts, however, the cause is different: messing up while reloading an M1 Garand semi-automatic rifle.

While Team Fortress 2 doesn’t directly acknowledge it in the game’s lore, the sniper class’s primary weapon is pretty clearly based on the iconic service rifle, albeit without the gas piston below the barrel and with a high-powered scope mounted on top. The most important similarity, however, is the bolt at the top of the rifle, which has a tendency to snap closed on inattentive shooter’s thumb when they try to reload their weapon.

For those who have a hard time picturing how exactly this happens, here’s a demonstration with an actual M1 Garand:

In short, the proper way to reload an M1 garand is to keep your hand up against the bolt when you push your clip of ammunition into the rifle. If you fail to do that, it will slam shut the moment the clip is inserted all the way, leading to a nasty bruise.

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