Thread: Getting ES down with 223

Originally Posted by ebf

@Pommy, what SD are you getting ?

It would also help to know how many shots in a typical string when you are measuring.

ES only looks at the outer edges of a series, it is a poor measure.

In my experience the major factors affecting low SD:
- Annealing / Neck tension
- Flash holes
- Primer selection

You're right. I take more notice of SD but in my best loadings get single figures on both. And yes, you can delude yourself with small sample size eg the classic cherry picked 3 shot group.

A bit on primer flash holes (using quality brass) I give them an internal debur when new and that's it.
Primer pockets depths - I used to uniform. Don't bother with quality brass.

Norma brass. I imported Norma 284W brass from the States when it was available a few years ago. Norma did a special run for one Yankee company. I did accurate measurements of the flash holes which are drilled. The flash holes are actually shaped like a vortex ie tapered and open out as they exit into the case. Maybe a bit of carefull thinking gone into this.
Don't know if the crop of Norma 284W that was recently available here had the same feature.