Sniper/DM scenes are always a favorite for me...So, it was no surprise when I was younger and fell in love with the m14/m1a, thanks in part to Black Hawk Dawn.
And of course, an '03 from Saving Private Ryan.
And lastly, Enemy at The Gates. Though I don't have a PU, I do have an m44. Not really hard to attain nor the main reason I own one it it was still a decent movie.
Personally, I feel like the shooting/historical accuracy in these movies was about as realistic as possible in these movies compared to many others.