Seating Depth 143-ELDX in 6.5 Creedmoor

[Lpart]

I am about to have a barrel chambered for a 6.5 Creedmoor (Bartlein 8 twist) and am trying to determine free bore. 3 bullets I am interested in using are the 143 ELD-X, 135 gr Berger Classic and 124 gr Hammer. Mag length is a significant issue. I have seated each bullet in a case to a COAL overall length of 2.80" which is standard. My mag is about 2.82. I have then measured each round to the ogive given identical COAL.. Results are:

143 ELD-X 2.165 a lot of bullet beyond the ogive on this one!
135 gr Berger 2.210
124 gr Hammer 2.204

If I have a reamer made that is based on the longest ogive measurement of 2.210 + .020 = 2.230 it would seem I may be ok. Longest jump would be the ELD-X at .059. I have found several posts on the internet saying they were getting good accuracy at .060 jump for 143. If I do that I can still experiment with deeper seating for the Berger and Hammer if needed.

Please tell me of the gaps in my reasoning.

Thank youl

 

[Greyfox]

I seat the Hornady ELD-x .075" off the lands which gives me a COAL of 2.10". Velocity using 42 gr of H4350 or 45.6 gr of H4831sc(compressed), Fed210M, a Hornady brass. This produces velocity in the 2710FPS range SD 5. Group size with either load is sub.25MOA.

 

[Edd]

The SAAMI freebore spec is .199".

On a SAAMI chamber, a 143 gr ELD-X bullet makes land contact at an OAL length of 2.901". The OAL of box of Hornady ammo I have measures 2.810".

A Hammer 124 gr makes contact at an OAL of 2.880". A good length for the cartridge, based on the position of the bearing surface on the case neck, is 2.775".