Scene in Russian (?) TV series

[Fred588]

I wonder why she did not use her rifle just like a stick to give her some leverage.

For the same reason that someone who should know better continues to charge headlong into a bog.

For what it's worth - I've been in those situations where there's water on top and plenty of bottomless mush underneath and not wanting to drop the gear I was carrying. Wearing boots or much else would have made the difference between getting across and not.

There is a universal (nearly) answer for why someone in a movie does something like this. "Because that's what it said in the script."

[some_writer_guy]

She's a sniper. It's like a mindset with soldiers, and to her, the rifle is more important than her life. It's actually realistic that she would go under, and try to save the weapon, or at least keep it from getting gunked up. I once tore the hell out of my elbows to keep from scratching my rifle when I fell on gravel. At least the gun didn't get a booboo.