Some good info I just posted on another 6.5x284 question. http://www.6mmbr.com/sixfive284.html

A .297 neck means you will have to turn necks slightly, is that what you want? The article recommends 0.299" for a no turn hunting rifle.

As far as free bore I would go with the shorter length as you mentioned shooting bullets less than 140 grains. I like the shorter neck as it leaves room to grow as the throat erodes and if it does not work then easy enough to lengthen it. With max loads you will be chasing the lands with as few as a 1000 shots or less.

Last edited by Tejano; 02/07/19.
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