Depending on the shotgun, it may or not be available.
Go to Browning.com and you can download a manual.
numrich gun parts has breakdown drawings and assembly steps
About $100
To get a parts breakdown you would need to take the shotgun into a gun store. The store will be able to provide an estimate, or order new parts.
Check on Numrich gun parts corp website.
Made from 1964-81. No breakdown on numbers I can find.
in good condition 75to100.oo
Shoot it about 2000 times without cleaning it. It will break down!!
Would need to know the model number, which is numeric. Your best bet is to take the gun to a gunsmith and let him show you how to field strip the shotgun.
Most likely, the pump shotgun you have is a model 10. Uncheckered wood, grooved slide, value is from 150 to 300 dollars.
you have to ask the blueprint fairy.
That was a slide action shotgun, not a rifle, and was obsolete before 1920. No 'blueprints' are available. What are you needing to accomplish? sales@countrygunsmith.net