Got some vertical stringing

[JFrank]

@South Prairie Jim - what was your reduction in agg score between not weight sorting primers vs. sorting? Or was it across the chronograph - how much did your ES shrink?

Even behind a Panda, I couldn’t shoot the difference in weight sorting BR2’s or 4’s, personally. I know it made me feel better that I had done everything I could think to do, but I couldn’t manifest objective improvement with it. I just felt more ownership of my bad groups.

No question about ownership, and I don’t have any personal numbers for right now as I’m just putting more emphasis on ignition this year with primer details/testing smack in the middle of conversation, I may never be able to apply direct correlation but I will certainly share my data whenever it becomes available rather than quoting others technics or findings that may not apply to my firearm.
Jim

 

[JFrank]

Actually you may see a trend in these groups, one sample is sorted with pockets uniformed and depth set at .004 crush the other no prep and set by feel.

 

[JFrank]

Here’s is some additional language
https://forum.accurateshooter.com/threads/vertical-dispersion-weighing-primers.4000685/page-13

 

[Varminterror]

Here’s is some additional language
https://forum.accurateshooter.com/threads/vertical-dispersion-weighing-primers.4000685/page-13

There’s data there which confirm for me why I don’t weight sort.

The lacking correlation between blast pressure and weight, followed by Dave M’s test of extreme spread vs. exact matching weight which shows LESS vertical with the extreme spread weight group… I just can’t get there…

Primer seating depth, or at least consistency thereof, I absolutely agree.

 

[JFrank]

No worries’
I would encourage folks to test a bit for themselves and see what makes sense for their program.
Jim
Added; In the IBS long range the aggregate groups can be so close between competitors that by the end of the weekend a couple fractions separates winning and loosing so it makes sense for me where in your playground not so much.

 

[Varminterror]

it makes sense for me

Even when I WAS shooting BR and F-class, I couldn’t derive any objective performance improvement.

The data shared in your linked thread above shows there isn’t an objective improvement.

It does also show a lot of guys prefer to do it, for their own peace of mind. Which is fine. But objectively, I’ve yet to find an experiment which could be repeated which proves weight sorting primers is anything more than the voodoo that many guys choose to do.

Are you trimming meplats and pointing bullets also? I had a chance to take some bullets across the Applied Ballistics mobile lab a couple of years ago. Their Doppler confirmed the improved consistency in BC by trimming and pointing. THAT objective test did convince me to change my mind about something I’d otherwise written off…

 

[JFrank]

I buy these and figure they are better than my measuring tools, I load them straight from the box.

https://vaportrailbullet.com/

 

[JFrank]

Here’s some additional reading material regarding vertical stringing for the OP or anyone else interested.

https://www.6mmbr.com/verticaltips.html

 

[Axis II]

Took the advice here and look what I did between gusts of wind. 200yards off a Caldwell front rest and rear bag. Pretty proud of myself other than the top left shot.