Gun Jamming With Sand Movie?!

Hey... I have no idea what this movie is off the top of my head...

But i remember seeing a movie before... where theys 2 guys... (both apparently on the same team...) and the other one fails to save his "partner"... And his excuse is "his gun jammed..."


But later on in the movie... The guy explains that that gun wouldn't jam.. and demonstraits this by pouring sand through it...

does anyone have any inclination of what movie this could be ?

Thanks

Andy

its been awhile since ive seen it but i think nic cage mentions something about sand not jamming a gun in Lord of War,not sure about the other part of your question tho