Failure to enforce the law is a major problem IMHO. Here is an example of what I mean..
A guy walks into a gun shop with a felony conviction. He fills out the US government form #4473, required to buy a gun from a federal firearms dealer. There are questions on form 4473 including "have you ever been convicted of a felony"? The guy checks the no box, because if he checks the yes box the dealer won't even call NICS. The guy signs the form which states that the form is truthful under penalty of perjury. NICS denies the transfer because the guy lied on his 4473 and actually does have a felony conviction. Now the FBI knows that this convicted felon who is prohibited from owning a firearm is actively trying to buy a firearm....This exact scenario played out 132,000 times in 2005 (and every day of every year since). Wow! The FBI must sure be busy tracking down these convicted felons who they know have at least committed perjury and likely have acquired a gun, huh? Wouldn't these bona fide criminal leads be a fairly high priority? Turns out not so much....
Highlights
Nearly 70 million background checks conducted under the
Brady Act through 2005; over 57 million since the
permanent provisions took effect
* 1.6% of the 8.3 million applications for firearm transfers
or permits in 2005 were rejected by the FBI (66,700
applications)or State and local agencies(65,200
applications).
* Among State and local checking agencies in 2005, 46% of all
rejections for firearm transfers (about 30,000 applications)
were due to a felony conviction or indictment.
* About 15% of State and local rejections(10,000 applications)
were due to a domestic violence misdemeanor conviction or
restraining order.
* The Bureau of Alcohol, Tobacco, Firearm and Explosive's(ATF)
field offices investigated 9,575 National Instant Criminal
Background Check System(NICS)denials that were referred by
the FBI in 2005.
* In 2005 agencies reported 1,400 arrests of persons denied
a firearm or a permit.
* In 2005 U.S. attorney offices accepted for prosecution 135
NICS denial cases investigated by ATF.
http://bjs.ojp.usdoj.gov/content/pub/ascii/bcft05.txt