260 AI Load Development

[fullbore]

Gday Everyone

Just done a OCW test at 100 yards for my newly build 260 AI.
Details are:
142 Sierra Match King, 0.010" Jump
Lapua Brass (fireformed)
Fed 210M Primers
H4831SC (2213SC in Aus)

Personally I feel I messed up 48gr group with a bad trigger press even before seeing the chrony numbers. Looking at the vertical on the target am I right in saying that I have a node from 47gr up to 48gr?

Velocitys are as follows
46gr 2762fps avg, 18 ES 9.6SD

46.5gr 2809fps avg, 10 ES 5.6SD

47gr 2819fps avg, 24 ES 13.2SD

47.5gr 2879fps avg, 40 ES 21.4SD

48gr 2906fps avg, 7 ES, 3.6SD

48.5gr 2935fps avg, 43 ES 21.9SD

 

[Ryridesmotox]

I would try a couple around the 48 mark, if I was doing it myself. 47.8, 48 (just to verify), 48.2 and maybe 48.4 and see what you have. I think 48 is a pretty safe bet there, and I would be happy with the velocities at 48. But I would want to see how much cushion I have before the deviations start getting larger.

 

[fullbore]

I would try a couple around the 48 mark, if I was doing it myself. 47.8, 48 (just to verify), 48.2 and maybe 48.4 and see what you have. I think 48 is a pretty safe bet there, and I would be happy with the velocities at 48. But I would want to see how much cushion I have before the deviations start getting larger.

Thanks mate Ill run another test with those charges and then from there Ill start to tinker with seating depths.

 

[spife7980]

I would test 47-47.5 in .1 increments.