The Gibraltar line of shotguns was made for Sears & Roebuck. More information about them is readily available via the internet.
your shotgun was made in 1906
That is a very early serial number!If you have a auto-5 12 gauge shotgun,then the year of manufacture is 1904.If you have a 16 gauge shotgun,then the year of manufacture is between 1910-1912.
Kessler. Only in business from 1951 to 1953.
date of manufacture is 1915
Standard 16 gauge shotgun shells.
Your winchester model 12 shotgun was made by winchester in 1953.
remington wingmaster 16 gauge
Browning.com has a sn function under customer service.
your Winchester model 12 shotgun was produced in 1915.
To my Knowledge Browning or for that matter any gunmaker has never made a 16 gauge shotgun with a 4in.chamber.In order to get the answer that you seek,you will need to include the model of Browning shotgun in question along with the serial number(to date the year of manufacture) and the overall condition of your shotgun.