Quote Originally Posted by jumpthestack View Post
What is the purpose of this little circular doohickey on the left side of the stock? I just got my CMP Garand which has this, and the various parts diagrams I've seen don't seem to say what this is.
Its the mount for the M1's grenade sight. In theory that little disk gets mounted into the stock and then the actual main sight is attached to that. The little markings allow the user to get the proper angle measurement to launch for a specific distance.



Lots of GI's just used the launcher without the sights because it was too much of a hassle to mount the sight and use it while being shot at.