you can just buy a new firing pin.  idk what the big deal is.

The most obvious issue with micro-stamping is, what if someone is planning to do harm or just wants to frame someone for a crime?

He simply goes to the range and collects some of your spent cases (or obtains spent cases some other way).  Then, he places those cases at the scene of a gun-related crime.  That puts the heat on the innocent gun-owner, possibly with enough weight to convict.  Now the crook is free and clear, thanks to the state and their short-sighted gun-control laws!   

I would bet they are not even planning on using this feature to solve any crimes.  I think they are doing it just to make it more costly, difficult, and complicated to own firearms.

Firearm microstamping, ballistic imprinting and ballistic engraving are all names given to a controversial[1] technology that has been developed with the goal of aiding in ballistics identification; it involves the use of laser technology to engrave a microscopic marking onto the tip of the firing pin and onto the breech face of a firearm. When the firearm is fired, these etchings are transferred to the primer by the firing pin and to the cartridge case by the breech face, using the pressure created when a round is fired. After the spent cartridges are ejected, these microscopic markings are imprinted on the cartridges, which can then be recovered by police and examined by forensic ballistics experts to obtain information to be used to trace the firearm through its life to the registered owner.[2] This technology was to be required in California starting in 2010, however, it is on hold and law enforcement is specifically exempt.[3] On May 17, 2013 California Attorney Kamala Harris announced that micro-stamping had cleared all technological and patenting hurdles and would be required on newly sold semiautomatics, effective immediately.

"This is not going to help solve crimes," C.D. Miche said. "It's easily defeated, easily wears out and can be used to lead police down false alleys" if the serial numbers are altered.

He simply goes to the range and collects some of your spent cases (or obtains spent cases some other way).  Then, he places those cases at the scene of a gun-related crime.  That puts the heat on the innocent gun-owner, possibly with enough weight to convict.  Now the crook is free and clear, thanks to the state and their short-sighted gun-control laws!   

So what happens if your firing pin breaks and you need to buy a new one?