ES of slower powders

[Alex Wheeler]

I think there is a difference between saying that the best ES usually doesn't line up with the best group vs ES doesn't matter. I too see that all the time, where my best group does not have the best ES.

However, I have seen very good close range groups with ES in the 50s. I don't trust a load like that and have never taken such a load to 1000 yds. My assumption is when the ES gets into the mid-20s and above that I'll see vertical at long range. I have never tested that.

Almost always, I find that good loads have ES in the mid 20s or less. So for me, a bad ES with a good group shows me that more tuning is needed.

That leads me to my question. Have you ever seen a load with an ES of say 50 shoot a good group at long range?

No, but I cant remember a load with 50 ft of es. Theres something wrong there.

 

[INTJ]

No, but I cant remember a load with 50 ft of es. Theres something wrong there.

I guess we really are in agreement then. We tune for group size, not ES. The best groups doesn't always have the best ES, but a bad ES is an indicator that something isn't right.

 

[gunsandgunsmithing]

What you are trying to offset exactly is the rate of rise in point of impact vs velocity increase, with a matching rate of decrease in downward muzzle harmonics which is a combination of frequency and amplitude. I am finishing a straight forward procedure to characterize this, and will report soon.

PC did cross mind mind in regard to what Alex was talking about and I agree with you, that rate of rise is likely what a major part in what determines how much velocity variation PC can cure. I still believe that to get the most pc possible, we'd be shooting something that looks quite different than what most of our guns look like. Center of gravity on all planes, I believe will have to factor in, as well as barrel and stock stiffness.