Brass Spring Back

[tunacan]

Have a quick question.

How much should your neck conform to the chamber dimensions after firing? I just built a 6.5x47 L with a .294 neck. Loaded round is .290

After firing my neck is .291

Typically my necks are close to the chamber dimensions after firing.

Any comments? Could my reamer dimensions be off a bit?

 

[Dans40X]

Exact dimensions are not obtained on your first fire forming.