I am the new owner of a 99 vintage M1A in very good condition with an apparent low round count.
The bolt stop (standard, not extended) functions normally with a mag installed, holding the bolt open reliably after the last shot.
However, if I set the stop by hand without a mag inserted, it does not retain the bolt reliably.
I can feel and see the stop "creep" a little bit after removing my thumb and the bolt will release and go into battery spontaneously when the rifle is handled or moved. Again, this is only an issue without a mag inserted.
I have not removed the bolt stop but I have visually inspected the face of bolt lug and the bolt stop contact surface and both appear in good serviceable condition with no visible wear.
I suspect the bolt stop spring may be the culprit (too long or strong?) but am not certain what the standard is, or what else should be checked.
The bolt stop (standard, not extended) functions normally with a mag installed, holding the bolt open reliably after the last shot.
However, if I set the stop by hand without a mag inserted, it does not retain the bolt reliably.
I can feel and see the stop "creep" a little bit after removing my thumb and the bolt will release and go into battery spontaneously when the rifle is handled or moved. Again, this is only an issue without a mag inserted.
I have not removed the bolt stop but I have visually inspected the face of bolt lug and the bolt stop contact surface and both appear in good serviceable condition with no visible wear.
I suspect the bolt stop spring may be the culprit (too long or strong?) but am not certain what the standard is, or what else should be checked.