As long as the golf ball launcher can not discharge any type of grenade or explosive, it is CA legal.
If it can discharge any type of grenade or explosive, then it would be illegal due to being considered a destructive device under CA laws. [PC 16460(a)(2)]
Destructive Device:
In order to be a Destructive Device, it needs to meet one of the following:
1. Fires fixed ammunition that is .60 or greater. [PC 16460(a)(3)]
2. Launches a bombs/grenades/rockets/missiles/etc. [PC 16460(a)(2)]
Also note that...
Because the golf ball launcher is installed on a firearm, using it to launch golf balls is only legal in areas where it is legal to discharge a firearm.
^Does not matter that only blanks are being used with it.
If it can discharge any type of grenade or explosive, then it would be illegal due to being considered a destructive device under CA laws. [PC 16460(a)(2)]
Destructive Device:
In order to be a Destructive Device, it needs to meet one of the following:
1. Fires fixed ammunition that is .60 or greater. [PC 16460(a)(3)]
2. Launches a bombs/grenades/rockets/missiles/etc. [PC 16460(a)(2)]
Also note that...
Because the golf ball launcher is installed on a firearm, using it to launch golf balls is only legal in areas where it is legal to discharge a firearm.
^Does not matter that only blanks are being used with it.
Comment