4mm = 0.157"
5mm = 0.197"

I used the smaller one.

My Smith had previously been tapped 6-48. The NECG sights are 6-48 undersize. The sight screwed in easily with just my fingers. I put a dab of clear nail polish in the threaded hole and screwed it home.

CraigF

Last edited by CraigF; 04/04/13 09:21 PM.

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