6.5 PRC Powder Charge/Velocity Ladder Test. No Flat Spot

[Phil Rizzo]

My first thought is that 0.6 grains interval is too large, hence the possibility to miss the "flat(ter)" portion of the curve. I used 0.2gr intervals for both Hornady ELD-X 143 and Berger EOL 156, and eventually found a couple "flatter" portions each to choose from. The rifles were 2 Tikka T3x CTR, they had practically identical chambers (quite a statement for manufacturing quality control).

And if you land in a happy spot try .1 gr both ways.
one tenth can matter a lot, even in big cases.

BUT a wider node is definitely preferable!

 

[RockyMtnMT]

We always seem to find the best loads when vel increase with each increase in charge weight is very predictable. I am guessing that with the nice 35 fps +- with each increase in charge you will see a nice load with low es. I am not much of a node hunter unless one slaps me in the face near the upper end of pressure. I would take your upper end load just down from pressure signs and tinker there with seating depth if needed to find best accuracy.