Sako 85 Carbon light 7mm rem mag data

Hi team, im looking to do the standard forum 162gr eldx in front of 70-72gr on 2217.

Just wondering if anyone here with an 85 has worked out the best overall length?

looks like the mag will allow 3.65" and when i push a round into a spend case and chamber it, it comes out at 3.45"

I would start at 20 thou jump and adjust from there if no good.