I went to the range today and used 2.820" for all of my 139gr Scenar loads.
Started at 41.0 grs of H4350, 41.5, 42.0 and 42.5. All with 5 shot groups. Federal gold medal large rifle match primers, Hornady 1x fired brass.
My 2 best groups were at 41.5, which gave a nice round .76" group. The 42.5 gr load gave a .83" group that tended to be vertical. Factory loads seem to do the same.
I did not check velocity yet.
The primers were a wee bit flatter with the 42.5gr load but nothing that made me not want to use that load again.
Those groups matched the accuracy that the factory 143 ELD X is giving me. Those are running 2655 fps out of a 26" barrel X Bolt.
I guess the next order of business is to play with COAL after I check velocity.
Interesting that no scope elevation adjustment is needed with the above loads and the factory ELD X load. Hand loads shot about 1/2" to the right though.
