What type of insurance?
Your Home Owners will cover many of the perils associated with the loss of Firearms (Fire, Wiind etc.) when they are in your home, basically the things your home is insured against. However, most (if not all) home policies have a sub-limit for theft (very low from $1500-$3000, usually). To get a greater sub-limit, you need to add a firearms rider to your home owners policy by listing all your firearms and better yet, having them appraised. These policies normally will carry over to your auto etc. for theft, as long as there is evidence of the theft (broken glass, jimmied door etc.), otherwise it is classed as a 'mysterious dissapearance' and that is usually NOT covered.
The Home Owners rider is a good first step, as well as a good gun safe.
I don't know beyond this level of coverage, I hope this info helped somewhat.
AJ