Chicago’s fourth annual Gun Turn-In program is taking place Saturday. But the down economy may affect efforts to get guns off the streets.

The  program lets people hand over firearms to police—no questions asked —in exchange for a pre-paid credit card. A BB gun gets you $10. An assault rifle gets you $100.

But that’s less than last year. Corporate contributions funding the program are down 62 percent. Still, Police Superintendent Jody Weis says he’s not worried.

WEIS: Well, I think we’ll still get a lot of weapons off the street. We’ll see.  But, in my book, these are almost like freebies, because they’re coming in, and we’re getting them out of the homes where they can fall into dangerous hands.

Weis says the Gun Turn-In has collected 18,000 firearms since it began in 2005.

It’s being held Saturday at 27 sites across Chicago.