Help Identify Missing Screw- Marlin 1894

[bballwizard05]

That explains why my 8-40 alllllllmost seems to work. Interesting.

[bballwizard05]

The screw sold by Numrich is 8-40, and does not work. By stroke of luck my friend found the screw sitting in a random drawer in garage. Now I'm determined to confirm it's thread pitch. What would be the best way to test if it is .157-40? Can't seem to find any support for that threading at local hardware shops

[thegiff]

Pitch gauge would be good. Otherwise put a caliper on it to measure diameter, then measure as many thread pitches as you can and divide by the spaces. inverse gets you threads per inch. Magnification helps a lot. Also you can use other screws as your pitch gauge, like a 4-40 screw of course.