Options for detachable magazines
Rules for detachable magazines
For people who prefer function over form, configuring a semiautomatic rifle to have no prohibited features allows them to use fully detachable magazines of any capacity. If a semiautomatic rifle does not have any of the prohibited features it can accept normal detachable magazines. An important note of caution is that it is easy to overlook a flash hider when assembling a featureless rifle. Make sure that you either have no muzzle device or a muzzle brake on a featureless rifle.
If a person legally possess large-capacity magazines, there are no restrictions on using those magazines with a featureless semiautomatic rifle.
The Monsterman Grip is a pistol grip alternative that allows AR or AK style rifles to be used with detachable magazines. The Monsterman Grip is not a pistol grip as it is defined in the California Code of Regulations. The CCR defines a pistol grip as "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 below the top of the exposed portion of the trigger while firing (CCR 5469 (d)). http://www.monstermangrip.com/images/albums/NewAlbum_1de38/1-08-1.jpg
The U-15 Stock is a pistol grip and stock alternative. It is not a pistol grip as it doesn't meet the definition of pistol grip from the CCR. Further it is not a "thumbhole stock" which is defined in CCR 5469 (e) as "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." There is actually no hole in the U-15 Stock which allows a thumb to penetrate into or through it. A photo of a U-15 equipped Off List AR-15
In June of 2008 the Department of Justice convinced a Solano County District Attorney to charge John Contos of Sonoma Firearms with offering to sell a prohibited Assault Weapon based on the theory that the U-15 was a thumbhole stock. The Calguns Foundation successfully defended Mr. Contos in People v. Contos which was dismissed by The People in December of 2008 when the District Attorney came to the conclusion that he could not meet his burden of proof to show that a U-15 was a thumbhole stock as defined in the CCR.
Some owners chose to keep and fire their AK style rifles without a pistol grip or other prohibited features. A different version of the same concept is the Russian American Arms (RAA) Saiga which is an unlisted sporterized AK style rifle. Note that it's earlier incarnation as a "Kalashnikov USA Hunter Rifle/Saiga" is a listed/named Assault Weapon while the RAA Saiga is not.
There are also purpose fit Monsterman Grips and adapters to fit the AR style Monsterman Grip to AK style rifles. http://www.monstermangrip.com/images/albums/NewAlbum_1de38/mmgakbtypc02.jpg