COL for loading Hornady 143 grain ELD-X 6.5 Creedmoor in 10T Rifle

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.

If you are touching the lands with an OAL from base to tip of bullet of 2.66" then you have a chamber issue. Savage is known for short chambering Creedmoor rifles. Or are you measuring from the base to ogive of the bullet?

Hornady loads their ammo for the .199 free bore SAAMI spec chambers. Their ammo will fit in these chambers with no problem.

You can't average the base to ogive measurement. Measure it again and use your most consistent measurement. I put the modified case in the chamber and move it around a little and make sure it is bottomed out. Hold it tight and loosen the rod and ease the bullet in to the lands. Try wiggling the case while extending the rod. The longest consistent measurement will be where the lands are located. I have heard of some Savage barrels being short to the lands. I have a Manson Creedmoor reamer and my 12FV is.020 longer to the lands than my reamer is. The reamer has a.199 freebore so my chamber must be about.220. There should be some chime in that have more experience with the LnL OAL gauge and about the short or tight chambers.
You have to use the same bullet as the bullet you are comparing it to. Different bullets all measure different. Even lot to lot with the same bullet. Even different within bullets from the same lot.

Once you get your bullet seated off the lands(wherever you want it) you can use your comparator to measure or you can lay another bullet beside the cartridge and see how far the bullet is seated in the case.

This video offers a different approach to finding the lands.

https://www.youtube.com/watch?v=TWmIwPwLyyg