I am preparing to begin load development load in 6.5 CM for my 10T rifle. My dilemma is overall length. I used the Hornady Lock n Load AOL gauge to measure. I picked a few different bullets and averaged a lot of measurements to get a distance to the lands of 2.66" to the lands. I was impressed by the variability each time attempted a measurement (learning curve?).

As a sanity check I measured a box of factory Hornady Whitetail Hunter 129 gr IB and found them to average 2.67".

So, precision loading being something I'm a little new to, this brings up a few questions I'm hoping someone can guide me on.

1. Is my chamber a little tight; or would Hornady be putting out cartridges just touching the lands?
I realizing I'm comparing with a lighter bullet of slightly different shape; and Hornady can't account for every manufacturer's chambers. I didn't pull a bullet to check where they were at in the OAL gauge.

2. Does anyone have any experienced they can share with me on their experiences with this bullet/rifle? in particular what overall length I should start my load at.

Any help would be appreciated.

Thank you.