The protagonist of The Rundown does this by way of necessity in the climax, given as he's managing to dual wield two pump-action shotguns.

No practical reason, just to look badass.

Ira, Harry and Wayne do this after killing one of the aliens in Evolution.

It's not even during a battle, he's just getting the gun ready stating, 'I believe in being prepared.'

Rick O'Connel does this in The Mummy (1999).

Doubly justified in that Linda Hamilton spent a lot of time working out in preparation for this role, and wanted to show off her newfound skill.

Sarah Connor does it at the end when shooting the T-1000 in the foundry justified in that her right arm is wounded (though she still uses it for support while firing).

At one point, he mistakenly flipcocked the non-prop shotgun and almost did break his fingers. The prop shotgun that Arnold Schwarzenegger carried for the scene had an enlarged loop on the lever, and a lighter aluminum barrel, allowing him to do the trick without breaking his fingers. Also justified by how mind-blowingly badass he looked doing it.

Justified in-universe by the T-800 having metal 'bones' in his fingers that can withstand the stress of this action.

While the T-800 is riding his motorcycle and chasing John and the T-1000 down the canal, he spins his lever-action Winchester 1887 to reload it.

In True Grit, he spins his lever-action shotguns to reload them on horseback.

His introduction in Stagecoach features him firing a warning shot then spin cocking his lever-action rifle.

John Wayne was known for doing this in his films.

Jean-Claude Van Damme does this a few times in Hard Target during the climactic battle inside an old warehouse.

elaborate version of this Chow Yun-fat's character, Sergeant Francis Li, attaches a string to his shotgun's pump handle and trigger, so he can fire it from cover, in what can best be described as a shotgun yo-yo.

The Hong Kong film Tiger On The Beat features an.

Cheech Marin's priest character in Machete does this with two shotguns simultaneously.

The Real Trailer, Fake Movie for Hobo with a Shotgun ends with a bloody, naked hobo pumping his shotgun this way.

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