The Sten was a blowback-operated submachine gun firing from an open bolt with a fixed firing pin on the face of the bolt. This means the bolt remains to the rear when the weapon is cocked, and on pulling the trigger the bolt flies forward under spring pressure, stripping the round from the magazine, chambering it and firing the weapon all in the same movement.
However, the current day semi auto version of the Sten has a different operating system, and does use a movable firing pin.
Find a good gunsmith or machinist
A firing pin that is mounted on/in a hammer
Firing Pin Block
What should Firing pin protrusion measure?
Like it says, the firing pin rotates as the action cycles.
By action of the hammer striking the firing pin, forcing it into the primer.
Firing pin is what strikes the back end of bullet igniting propellant
Try e-gunparts.com
You can find a firing pin for the ranger at Numerick Gun Parts Corporation.
I am looking for a firing pin for a Crescent Firearm I believe the serial # is 8894
How to replace a firing pin from a Charles Daly 20-gauge semi automatic
To remove the firing pin from a Ruger P89, first ensure the firearm is unloaded and the magazine is removed. Disassemble the pistol by removing the slide from the frame, then take out the recoil spring and barrel. Next, locate the firing pin retaining pin at the rear of the slide, remove it, and then carefully pull out the firing pin along with the firing pin spring. Always follow safety protocols and consult the owner's manual for specific instructions.