A new law headed to the governor’s desk for signature would force California gun owners to ask the state permission to build their own firearms and pay a fee for background checks and registration.

Sponsored by Democratic state Rep. Kevin DeLeon — famous for his “ghost gun” press conference claiming home-built AR-15s had “30-caliber clips” and could fire 30 rounds in .5 seconds — the bill would require Californians to apply to the state Department of Justice for a registration number before they build a firearm and, if granted, permanently affix the registration number to the gun based on federal guidelines.

Dubbed SB 808, the bill would also mandate builders to embed “3.7 ounces of material type 17-4 PH stainless steel” into any home-built polymer lower receiver.

“Technological advancements require that we update our laws to meet new and growing public safety concerns to make sure dangerous individuals cannot manipulate technologies at the expense of public safety,” DeLeon said in a statement.

The move is the latest effort by gun control advocates to address what they consider a loophole in laws governing personal firearm manufacturing.

According to federal regulations, a person may manufacture a firearm for his own use without obtaining a serial number or background check as long as certain finishing criteria are met. Enthusiasts of AR-style rifles have recently seen a surge in companies offering so-called “80 percent lowers” that most home builders can mill out with hand tools and build into a completed rifle without registering them with the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Gun rights advocates in California are furious over DeLeon’s bill and are urging their allies to fight the bill.

“In spite of the fact that some lawmakers refuse to accept the realities of our human condition, not all of life’s problems can be solved with new fees, expanded bureaucracies, and increased penalties,” the California Association of Federal Firearms Licensees wrote in a release. “Californians should take no solace in the fact that SB 808 will not keep guns out of the hands of prohibited criminals, nor should they feel safe knowing that elected representatives like Senator de Le?n choose to play politics with irrational and irresponsible bills like SB 808 rather than take on the issues that matter.”

If signed by California Gov. Jerry Brown, SB 808 could mean the end of the 80 percent lower market in the state. The bill comes just months after Oceanside, California-based Ares Armor was targeted by the ATF over concerns that the 80 percent polymer lowers the company sold did not meet federal standards for home builds. Ares does not sell completed lowers that require a serial number.

Though Brown has been a longtime advocate of gun control, he has vetoed bills that would tighten some state firearms laws. Also on his desk for signature is a bill dubbed the “Gun Violence Restraining Order” law that would allow California police to seize firearms if a judge says the owner is a danger to himself or others.