Re: Question on barrel threading
There you go...no more guessing.
Redneck,
1. Thread gauges are a tool used by competent and responsible gunsmith's to determine that the correct diameter and thread pitch are held in all instances. It is a simple tool to use, but reasonably expensive to purchase. When we think of threading a barrel, we think of it in terms of:
- Is the thread cut in the correct handedness (or rotational direction, Right or Left)?
- Are the threads being cut to the right diameter? The major diameter and the minor diameter and the mean of those two, known as the pitch.
The gauges can check that as well as lead-in and more (depth, classes of fit, etc.) Good suppressor companies use gauges when they finish cutting your internal threads and your barrel threading should be equally concerned with the uniformity and correctness shown in your can.
2. Shoulder - The formation of the shoulder is very important. In fact a good shoulder can make up for some minor failings in threading. A good shoulder will allow the can to mate up in perfect alignment to the required can bore and supply the contact required for the right lock-up. You would not believe some of the barrel shoulders (or lack thereof) I see.
3. The third item is all about what constitutes the true center of bore of both the barrel and the can. A bad thread job references the outside of the barrel as the determinant in cutting the threads. Since we know that the bore does not always exactly finds its way to the true center of the barrel, we want to center off the internal "bore" dimension and rework, if required, and issues found with the outside dimensions of the barrel.
