Since I know you're a proponent of shared knowledge, what tips would you give concerning chamber reaming techniques? I've read your info on the importance of controlling throat diameter, but how do you achieve this?

In a nutshell, you cannot hold tolerances in the tenths of a thous. with all the torque forces on the reamer cutting the whole chamber body. You have to throat separately, and that is why I go to the extent I do explaining this on my website.

Pilots have to have clearances. Bore diameters vary quite a bit. Thus you never can rely on the pilot to hold the reamer in line and not wallow the throat dimension.

Add to that the fact that most barrels have a marked curvature in the bores, especially the factory barrels. Conversely, those with the least runout and straightest bores are the Virgin Valley barrels, good ones. But most of the others have quite a bit of runout.

The bore may be centered at the extreme breech end, but by the time the reamer gets into the chamber an inch or two, the bore is no longer centered with the axis of the lathe and the reamer. Thus the front end of the reamer is trying to follow a point off axis with everything else and is wallowing rather than cutting its true diameter or the diameter it would if the hole were centered.

I feel that no matter how the body of the chamber is cut, the throat should always be cut separately and as the vary last operation, independent of the effects of the forces present cutting the body of the chamber.

Keep the throat DIAMETER down to the bare bones minimum, just a very few tenths over normal bullet diameter for the caliber being chambered, and use a long leade angle.

There are a lot of various techniques, but the key is the throat.

Mike

Thanks Mike,
It's great to learn from "the master"!