LOS ANGELES (CBSLA.com) — A controversial gun measure proposed by a Southern California lawmaker that would require background checks for all ammunition purchases statewide is moving forward in Sacramento.

Senator Kevin de León (D-Los Angeles) first introduced Senate Bill 53 last December, which would require anyone wishing to purchase ammunition in California to first obtain a Ammunition Purchase Permit issued by the Department of Justice, valid for one year from the date of issuance.

READ MORE: Federal Court Rules Closure Of Gun Shops At Start Of Pandemic Unconstitutional

To obtain such a permit, the holder would have to pass a traditional background check as well as a mental health check, according to De León. The legislation would also ban online and mail order sales of ammunition to Californians.

In addition, SB 53 would require all ammunition sales to take place at a limited list of State-approved “ammunition vendors”, who would also be required to submit sales records to the CA Department of Justice.

But De León told KNX 1070 NEWSRADIO the legislation is intended to address an apparent loophole in California law that allows anyone – including convicted felons – to buy ammunition just about anywhere.

READ MORE: USC To Require Security Guards In Hallways And Stairs Leading To Bedrooms During Fraternity Parties

“If you get out of Men’s Central Jail, or let’s say Pelican Bay or San Quentin prison, you can walk into any gun store in California and you can load up a U-Haul truck, fill it up with ammunition, you can drive to South Central Los Angeles…and sell all the ammunition you want on the black market,” he said.

De León had previously backed AB 962, known as the Anti-Gang Neighborhood Protection Act, which sought to regulate handgun ammunition and was signed by Governor Schwarzenegger in 2009. AB 962 has since been tied up in legal challenges from the National Rifle Association (NRA).

The NRA has also publicly opposed SB 53 (PDF), which the group alleges would “encompass all hunting rounds that have no association with crime whatsoever.”

MORE NEWS: Authorities Searching For Missing Temple City Man

SB 53 passed in the state Senate by a 23 to 15 vote on May 29. The bill was scheduled to be heard by the state Assembly on Tuesday.