It depends on the brand and model. Check with the manufacturer for an owner's manual.
Follow instructions in the owner's manual. Find a gunsmith.
You will need a gunsmith to show you.
Try your local gun smith.
For a drawing of the parts, see the link below.
not difficult to do, but tricky to re-assemble correctly. Best to find someone familar with lugers to show you how to take apart and put back together. like a gunsmith....
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See the link below for the Crosman version.
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