Evolution of a Load

[Lapua40X]

Working on a new load today and learned how a wide range of variables can remain relatively constant while fine tuning just one can make a great deal of difference.
My loads (6BR Norma 107 gr Sierra MK in turned neck cases with about .001 neck tension) were set at 28 gr. Varget. The single change I made for today's tests was seating depth.
My chamber measures 1.812 to the lands. With the OAL at the ogive set with clearances of:
.024 to the lands I recorded MV ES 14 with an average of 2613 fps and a group dispersion of .747
.017 to the lands I recorded MV ES 22 with an average of 2616 fps and a group dispersion of .507
.012 to the lands I recorded MV ES 18 with an average of 2621 fps and a group dispersion of .314
The linearity of the results surprised me and, I think, lends credence to the things I've learned from the experienced guys in this forum. Wanted to offer my thanks for their contributions

 

[338 Mollett]

Interesting how velocity spreads tell you one thing and the barrel harmonics tell you another.Glad you found the node !