Copied and pasted from MS website

1992 was also the first year to use a .577 Nitro Express double rifle and I wanted to see what effect its 750 grain bullets travelling at 2150 feet per second would have on buffalo. To my surprise, it produced less than expected results and I soon learned an important lesson. It's not the size or speed of the bullet that counts, but where it's placed.

1996, This is also the first year that I used a .600 Nitro Express double rifle and its 900 grain bullets. The effect this gun has on game must be seen to be believed.

"Death at my feet" filmed around 2000? IIRC
Using my much trusted and beloved .600 Nitro Express double rifle and its 900 grain bullets, Death At My Feet features two extraordinary buffalo charges and one incredible rogue bull hippo charge with all three beasts dropping dead at my feet

"Death by the ton" (released 2004 or 2005)
In this movie you will see me hunting with a number of fine double rifles. My favorite, of course, is the .600 Nitro Express shooting 900 grain fist-sized bullets at 2,000 feet per second. I also use a beautiful Charles Osborn .577 (750 grain bullets) and a .500 Nitro Express (570 grain bullets) made by William Evans of London.

In his latest movie filmed in 2005 "Death Rush"
He states that he was using his 577 nitro with 750 gr bullets. page will not let me copy and paste.
http://www.nitroexpresssafaris.com/

I have only seen the previews for his movies, so I have no opinion but it's amusing. 40+ dollars a movie is too steep for me to pay.

PS- If anyone has a copy I will be glad to review it

Johnson