You have a Marlin Model 19-G that would have been made sometime between 1916 and probably 1918. (maybe as late as 1921, but I would doubt it)
The Model 19 is a takedown action with a pistold grip stock. The Model 19-G is an improved version of the Model 19, that was made from 1906 to 1907.
You need to be very careful when shooting these old Marlin shotguns. Marlin has issued a Service Bulletin advising owners of these old pump action shotguns NOT to shoot them The action is somewhat complicated and unless EVERYTHING inside is in correct working order, the breech bolt can be released from the action upon firing. (think where your head is when you shoot!) There is a website that gives the instructions to check the safety actions and you should take your gun through the steps outlined to check it.
You should be able to do a search on our website to find the above mentioned website.
I hope this helps, and good luck
Due to the increasing cost of ammunition, there be no warning shot!
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