For purposes of Penal Code section
Articles 2 and 3 of this Chapter the following definitions shall apply:
(a) "Ability to accept a detachable magazine"
means with respect to a semiautomatic shotgun, it does not have a fixed
(b) "Action" means the
working mechanism of a semiautomatic firearm, which is the combination of the
receiver or frame and breech bolt together with the other parts of the
mechanism by which a firearm is loaded, fired, and unloaded.
(c) "Barrel" means the tube, usually metal
and cylindrical, through which a projectile or shot charge is fired. Barrels
may have a rifled or smooth bore.
(d) "Barrel length" means the length of the
barrel measured as follows: Without consideration of any extensions or
protrusions rearward of the closed bolt or breech-face the approved procedure
for measuring barrel length is to measure from the closed bolt (or breech-face)
to the furthermost end of the barrel or permanently attached muzzle device.
Permanent methods of attachment include full-fusion gas or electric steel-seam
welding, high-temperature (1100o F) silver
soldering, or blind pinning with the pin head welded over. Barrels are measured
by inserting a dowel rod into the barrel until the rod stops against the closed
bolt or breech-face. The rod is then marked at the furthermost end of the
barrel or permanently attached muzzle device, withdrawn from the barrel, and
(e) "Bullet" means the
projectile expelled from a gun. It is not synonymous with a cartridge. Bullets
can be of many materials, shapes, weights, and constructions such as solid
lead, lead with a jacket of harder metal, round-nosed, flat-nosed,
hollow-pointed, et cetera.
"Bullet-button" means a product requiring a tool to remove an ammunition
feeding device or magazine by depressing a recessed button or lever shielded by
a magazine lock. A bullet-button equipped fully functional semiautomatic
firearm does not meet the fixed magazine definition under Penal Code section
(g) "Bore" means the interior of a firearm's
barrel excluding the chamber.
"Caliber" means the nominal diameter of a projectile of a rifled firearm or the
diameter between lands in a rifled barrel. In the United States, caliber is
usually expressed in hundreds of an inch; in Great Britain in thousandths of an
inch; in Europe and elsewhere in millimeters.
(i) "Cartridge" means a complete round of
ammunition that consists of a primer, a case, propellant powder and one or more
(j) "Centerfire" means
a cartridge with its primer located in the center of the base of the
(k) "Contained in" means that
the magazine cannot be released from the firearm while the action is assembled.
For AR-15 style firearms this means the magazine cannot be released from the
firearm while the upper receiver and lower receiver are joined
(l) "Department" means
the California Department of Justice.
"Detachable magazine" means any
ammunition feeding device that can be removed readily from the firearm without
disassembly of the firearm action or use of a tool. A bullet or ammunition
cartridge is considered a tool. An ammunition feeding device includes any
belted or linked ammunition, but does not include clips, en bloc clips, or
stripper clips that load cartridges into the magazine.
An AR-15 style firearm that has a bullet-button style
magazine release with a magnet left on the bullet-button constitutes a
detachable magazine. An AR-15 style firearm lacking a magazine catch assembly
(magazine catch, magazine catch spring and magazine release button) constitutes
a detachable magazine. An AK-47 style firearm lacking a magazine catch assembly
(magazine catch, spring and rivet/pin) constitutes a detachable
of the firearm action" means the fire control assembly is detached from the
action in such a way that the action has been interrupted and will not
function. For example, disassembling the action on a two part receiver, like
that on an AR-15 style firearm, would require the rear take down pin to be
removed, the upper receiver lifted upwards and away from the lower receiver
using the front pivot pin as the fulcrum, before the magazine may be
(o) "Featureless" means a
semiautomatic firearm (rifle, pistol, or shotgun) lacking the characteristics
associated with that weapon, as listed in Penal Code section
(p) "Fixed magazine" means an ammunition
feeding device contained in, or permanently attached to, a firearm in such a
manner that the device cannot be removed without disassembly of the firearm
(q) "Flare launcher" means
a device used to launch signal flares.
(r) "Flash suppressor" means any device
attached to the end of the barrel, that is designed, intended, or functions to
perceptibly reduce or redirect muzzle flash from the shooter's field of vision.
A hybrid device that has either advertised flash suppressing properties or
functionally has flash suppressing properties would be deemed a flash
suppressor. A device labeled or identified by its manufacturer as a flash hider
would be deemed a flash suppressor.
(s) "FMBUS" means a Firearm Manufactured By
pistol grip" means a grip that allows for a pistol style grasp forward of the
(u) "Frame" means the
receiver of a pistol.
launcher" means a device capable of launching a grenade.
(w) "Permanently attached to" means the
magazine is welded, epoxied, or riveted into the magazine well. A firearm with
a magazine housed in a sealed magazine well and then welded, epoxied, or
riveted into the sealed magazine well meets the definition of "permanently
(x) "Overall length
of less than 30 inches" with respect to a centerfire rifle means the rifle has
been measured in the shortest possible configuration that the weapon will
function/fire and the measurement is less than 30 inches. Folding and
telescoping stocks shall be collapsed prior to measurement. The approved method
for measuring the length of the rifle is to measure the firearm from the end of
the barrel, or permanently attached muzzle device, if so equipped, to that part
of the stock that is furthest from the end of the barrel, or permanently
attached muzzle device. (Prior to taking a measurement the owner must also
check any muzzle devices for how they are attached to the barrel.)
(y) "Pistol" means any device designed to be
used as a weapon, from which a projectile is expelled by the force of any
explosion, or other form of combustion, and that has a barrel less than 16
inches in length. This definition includes AR-15 style pistols with pistol
buffer tubes attached. Pistol buffer tubes typically have smooth metal with no
guide on the bottom for rifle stocks to be attached, and they sometimes have a
foam pad on the end of the tube farthest from the receiver.
(z) "Pistol grip that protrudes conspicuously
beneath the action of the weapon" means a grip that allows for a pistol style
grasp in which the web of the trigger hand (between the thumb and index finger)
can be placed beneath or below the top of the exposed portion of the trigger
while firing. This definition includes pistol grips on bullpup firearm
(aa) "Receiver" means the
basic unit of a firearm which houses the firing and breech mechanisms and to
which the barrel and stock are assembled.
(bb) "Receiver, lower" means the lower part
of a two part receiver.
"Receiver, unfinished" means a precursor part to a firearm that is not yet
legally a firearm. Unfinished receivers may be found in various levels of
completion. As more finishing work is completed the precursor part gradually
becomes a firearm. Some just have the shape of an AR-15 lower receiver for
example, but are solid metal. Some have been worked on and the magazine well
has been machined open. Firearms Manufactured by Unlicensed Subjects (FMBUS)
began as unfinished receivers.
"Receiver, upper" means the top portion of a two part receiver.
(ee) "Rifle" means a weapon designed or
redesigned, made or remade, and intended to be fired from the shoulder and
designed or redesigned and made or remade to use the energy of the explosive in
a fixed cartridge to fire only a single projectile through a rifled bore for
each single pull of the trigger.
(ff) "Rimfire" means a rimmed or flanged
cartridge with the priming mixture located in the rim of the case.
(gg) "Second handgrip" means a grip that
allows the shooter to grip the pistol with their non-trigger hand. The second
hand grip often has a grip texture to assist the shooter in weapon
a firearm functionally able to fire a single cartridge, eject the empty case,
and reload the chamber each time the trigger is pulled and released. Further,
certain necessary mechanical parts that will allow a firearm to function in a
semiautomatic nature must be present for a weapon to be deemed semiautomatic. A
weapon clearly designed to be semiautomatic but lacking a firing pin, bolt
carrier, gas tube, or some other crucial part of the firearm is not
semiautomatic for purposes of Penal Code sections
(1) A mechanically whole semiautomatic
firearm merely lacking ammunition and a proper magazine is a semiautomatic
(2) A mechanically whole
semiautomatic firearm disabled by a gun lock or other firearm safety device is
a semiautomatic firearm. (All necessary parts are present, once the gun lock or
firearm safety device is removed, and weapon can be loaded with a magazine and
regards to an AR-15 style firearm, if a complete upper receiver and a complete
lower receiver are completely detached from one another, but still in the
possession or under the custody or control of the same person, the firearm is
not a semiautomatic firearm.
stripped AR-15 lower receiver, when sold at a California gun store, is not a
semiautomatic firearm. (The action type, among other things, is
"Shotgun with a revolving cylinder" means a shotgun that holds its ammunition
in a cylinder that acts as a chamber much like a revolver. To meet this
definition the shotgun's cylinder must mechanically revolve or rotate each time
the weapon is fired. A cylinder that must be manually rotated by the shooter
does not qualify as a revolving cylinder.
(jj) "Shroud" means a heat shield that is
attached to, or partially or completely encircles the barrel, allowing the
shooter to fire the weapon with one hand and grasp the firearm over the barrel
with the other hand without burning the shooter's hand. A slide that encloses
the barrel is not a shroud.
"Spigot" means a muzzle device on some firearms that are intended to fire
grenades. The spigot is what the grenade is attached to prior to the launching
of a grenade.
(ll) "Stock" means
the part of a rifle, carbine, or shotgun to which the receiver is attached and
which provides a means for holding the weapon to the shoulder. A stock may be
fixed, folding, or telescoping.
(mm) "Stock, fixed" means a stock that does
not move, fold, or telescope.
"Stock, folding" means a stock which is hinged in some fashion to the receiver
to allow the stock to be folded next to the receiver to reduce the overall
length of the firearm. This definition includes under folding and over folding
(oo) "Stock, telescoping"
means a stock which is shortened or lengthened by allowing one section to
telescope into another portion. On AR-15 style firearms, the buffer tube or
receiver extension acts as the fixed part of the stock on which the telescoping
butt stock slides or telescopes.
(pp) "Those weapons with an ammunition
feeding device that can be readily removed from the firearm with the use of a
tool" includes functional semiautomatic rifles, pistols, and shotguns with
bullet-button style magazine releases. These weapons do not have a fixed
(qq) "Thumbhole stock"
means a stock with a hole that allows the thumb of the trigger hand to
penetrate into or through the stock while firing.
(rr) "Threaded barrel, capable of accepting a
flash suppressor, forward handgrip, or silencer" means a threaded barrel able
to accept a flash suppressor, forward handgrip, or silencer, and includes a
threaded barrel with any one of those features already mounted on it. Some
firearms have "lugs" in lieu of threads on the end of the barrel. These lugs
are used to attach some versions of silencers. For purposes of this definition
a lugged barrel is the same as a threaded barrel.