"It’s a fantastically complex and demanding task, and the barrel maker’s attention to fine detail is extremely important to good future accuracy. You can have the most highly engineered action, the most expensive stock, the most sensitive of triggers, and a well proven load, but if they’re matched up with a so-so barrel, you’ve got problems. All that aside, the more you know about barrel making, the better the questions you can ask when shopping for your next re-barrel job. Let’s take a look at how it all gets done."

http://www.lasc.us/RangingShotBarrelMakingFeature.htm