Bullet Runout

[xsn10s]

I think your 550 yard steel group is missing in the post.

Yup here's the 550 yard group. I get woke up two to three times a night caretaking. And I work so sometimes I'm a bit off in the mornings.

 

[xsn10s]

I don't shoot a lot of groups after I finish working up loads. I'll shoot to distance and then take them out hunting. Both of these are coldbore hits. The rock chuck was at 533 yards. The badger was 659 yards. Both with my budget build 260 AI. 145 gr Match Burners. So yeah making ammo with the least amount of runout is desirable. But it's not the end all be all.

 

[Mikecr]

The Sinclair (like many others) measures runout from case neck to bullet tip.

No, the Sinclair does not measure runout from necks to tips.
V-blocks measure full length total runout. They don't conceal anything.

The neck benders pin both ends and indicate very near one side. This, showing very little of actual total runout.
Think arc measure of a spinning jump rope. You would properly measure in the middle of arc, NOT at one pinned end.

Your ammo is not straight until it measures so on a v-block gauge.