.280 ai load development

[brandon327]

Has anyone had to redo load development after 150 rounds? I did my initial load development at 50 rounds and now it will not hold a group. It has gone from 1/2" groups to 2"groups. It has sped up according the chrono.

 

[elkaholic]

Thats not too unusual, depending on the barrel. If you redo it now, it will likely stay.

 

[brandon327]

I did a 10 shot load development test and the velocity sweet spot is still in the same place. I was 2999 before and today it was 3000. The previous data had a ES of 12 and today's data had a ES of 6. It took 1.2 grains of powder less to achieve the same velocity.