Thanks for the info. The rifle I am working on has extraction issues due to an obstruction of some sort at the end of the neck area in the chamber. That's causing a neck pinch that is visible on the brass. Trimming back the brass about 15 thou solves the problem. I suspect a chunk of brass has become lodged there and a brush isn't getting it out. The gunsmiths around here have not been any help for various reasons. Seems no one wants to work on these due to their reputation alone. This old 742 carbine is in great condition and is quite a shooter for it's short barrel.