03-13-2011, 02:55 PM
Obviously I cannot verify which upper this is from the screen name but it should be on the way back. Please call Melissa on Monday for tracking info.
Misalignment of the planes of locking lugs on the barrel and the bolt will create stresses which will accelerate failure. The front face of the reciever can cause this probem. Loose fitting barrel extension to reciever joints allow movement in angular and axial planes which is always a problem, if only with accuracy. Barrel extensions should be checked for thread to locking face alignment and most importantly should only be installed once. Removal of the barrel extension and reinstalling will often shift how they mate. Military tightening specifications will plastically deform the barrel threads and shoulder and must not be used for best builds.
One of the goals of the enhanced bolt system we make is to reduce the sensitivity to alignment. We are currently in a slight redesign to improve the stress raisers at the extractor cut and the durability of the spring. The heat treatment is being examined to see if newer methods can yield a more effective overall design.
Bill Alexander
Misalignment of the planes of locking lugs on the barrel and the bolt will create stresses which will accelerate failure. The front face of the reciever can cause this probem. Loose fitting barrel extension to reciever joints allow movement in angular and axial planes which is always a problem, if only with accuracy. Barrel extensions should be checked for thread to locking face alignment and most importantly should only be installed once. Removal of the barrel extension and reinstalling will often shift how they mate. Military tightening specifications will plastically deform the barrel threads and shoulder and must not be used for best builds.
One of the goals of the enhanced bolt system we make is to reduce the sensitivity to alignment. We are currently in a slight redesign to improve the stress raisers at the extractor cut and the durability of the spring. The heat treatment is being examined to see if newer methods can yield a more effective overall design.
Bill Alexander