November 30th, 2016, 09:07 AM
Join Date: May 2006
Location: kerrville. texas
M14/M1A trigger housing.
The M14 trigger housing [TH] is usually easier to install into the receiver than those in the M1 Garands, it is a straight push in, close up the guard.
The M1A commercial TH can be another matter to install.. The problems are easy to correct in most cases. Sometimes there are rough edges left on the receiver TH slot, combined with the same on the spline of the TH itself. These edges can be stoned smooth, add a small amount of lube and fit the splin into the slot, push up and close..
Lately, M1A's have been appearing where someone has taken the time to stake the TH spline, a series of distoring gouges along the both sides of the original shape. At some point someone decided the fit between the spline and slot should be tight, that is incorrect, and can cause issues of alignment followed by malfunctions.
The fit should be loose enough to allow a rocking movement front to rear. It is this movement that allows the TG to seek the proper position relative to the receiver.
Another issue regarding the TG is the vertical fit to the receiver. Using M1A commercial parts where one piece is slightly out of spec one way and the other parts is slightly out of spec the other way might cause the TG to insert too deep or too shallow.. Both of these conditions require a fix.
Too deep can be overcome by adding shims under the bedding pads of the trigger guard. This happens often when using an old GI wood stocsk that has be refinised several times... Too shallow requires removeing surface material under the bedding pads. Go sloooow in removing this material, stop and check fit often... Stop as soon as heel of the hand is required to close the guard...
Hope this helps solve any issues you are troubled with... Art