Help me figure out what's going on. Changing ES and SD - Reloading Methodology https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/ AllGunStuff Discussion Board en-US Fri, 08 May 2026 14:22:46 +0000 wpForo 60 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/paged/2/#post-2567 Wed, 07 Jun 2023 13:16:04 +0000

I got what I consider to be fudged chrony readouts, usually my chrony will indicate 'dup' if a velocity repeats, but I had some shots just keep displaying the previous number, and all I can think of in my case is there was too much muzzle blast at five meters. I think I must go to 10 meters for 100+ grains of powder.


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10 m, ?????????????????????? lot a folk shooting revolvers will find the chroni being hit ever so often  ;D  ;D  ;D  ;D  ::) I see some very wide results at the range with 38/357 owners, very wide and very high low.


Those who have difficulty shooting the bullets through the sky screens, could always place some bullet proof objects in front of the chrony's "vitals".  An angled plate, for example, may help to prolong it's useful life span.]]> Reloading Methodology 223 https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/paged/2/#post-2567 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2560 Tue, 06 Jun 2023 12:30:53 +0000 I got what I consider to be fudged chrony readouts, usually my chrony will indicate 'dup' if a velocity repeats, but I had some shots just keep displaying the previous number, and all I can think of in my case is there was too much muzzle blast at five meters. I think I must go to 10 meters for 100+ grains of powder.


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10 m, ?????????????????????? lot a folk shooting revolvers will find the chroni being hit ever so often  ;D  ;D  ;D  ;D  ::) I see some very wide results at the range with 38/357 owners, very wide and very high low.]]> Reloading Methodology Treeman https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2560 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2556 Tue, 06 Jun 2023 12:01:14 +0000

What caliber is it, and how far is the chrony from the muzzle ?

I got what I consider to be fudged chrony readouts, usually my chrony will indicate 'dup' if a velocity repeats, but I had some shots just keep displaying the previous number, and all I can think of in my case is there was too much muzzle blast at five meters. I think I must go to 10 meters for 100+ grains of powder.


6.5 Creedmoor. About 3m from the muzzle. Definitely something to consider


To keep my cheap Chrony out of the blast zone, I place it 3m away from the muzzle when testing handguns with fast-burning powder.
Magnum handguns with slow-burning powder and small to medium rifle loads 5m at least.
Large caliber rifle loads (375 and up) and those using slow-burning powder (7mm Rem Mag, 300, 338 LM etc) I test at 10m from the muzzle.  With a brake or suppressor 5 m should be good.

All this is to allow the bullet to pass over both sky screens before the blast wave or some un-burnt powder granules reach the first sky screen.]]> Reloading Methodology 223 https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2556 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2553 Tue, 06 Jun 2023 10:32:01 +0000

What caliber is it, and how far is the chrony from the muzzle ?

I got what I consider to be fudged chrony readouts, usually my chrony will indicate 'dup' if a velocity repeats, but I had some shots just keep displaying the previous number, and all I can think of in my case is there was too much muzzle blast at five meters. I think I must go to 10 meters for 100+ grains of powder.


6.5 Creedmoor. About 3m from the muzzle. Definitely something to consider

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I usually after some bad readings take 3 large strides, those stretch steps these days, closer to 5 m than 3 m likely somewhat over 4 m, that plus fresh batteries of reputable brand will be a very good start to eliminating faults outside of the rifle and load..]]> Reloading Methodology Treeman https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2553 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2552 Tue, 06 Jun 2023 10:23:02 +0000
What caliber is it, and how far is the chrony from the muzzle ?

I got what I consider to be fudged chrony readouts, usually my chrony will indicate 'dup' if a velocity repeats, but I had some shots just keep displaying the previous number, and all I can think of in my case is there was too much muzzle blast at five meters. I think I must go to 10 meters for 100+ grains of powder.


6.5 Creedmoor. About 3m from the muzzle. Definitely something to consider]]> Reloading Methodology jager https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2552 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2551 Tue, 06 Jun 2023 10:00:58 +0000
I got what I consider to be fudged chrony readouts, usually my chrony will indicate 'dup' if a velocity repeats, but I had some shots just keep displaying the previous number, and all I can think of in my case is there was too much muzzle blast at five meters. I think I must go to 10 meters for 100+ grains of powder.]]> Reloading Methodology 414gates https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2551 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2547 Tue, 06 Jun 2023 07:34:11 +0000
Is the powder batch number the same for the low and higher ES loads ?


Yep. Same tin even.

I'm beginning to think it has a lot to do with a dodgy chrono.  Tried some new loads with graphite lube in the necks, slight improvement. But not massive. 

Anyway, the rounds are accurate enough (about 1MOA) for hunting, so will be using my current loads during this hunting season and work up some new loads in the spring.]]> Reloading Methodology jager https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2547 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2541 Mon, 05 Jun 2023 14:09:17 +0000 Reloading Methodology 414gates https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2541 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2488 Sat, 20 May 2023 00:40:42 +0000
1. Clean case neck making contact with clean bullet shank.  Yes, there may be some form of reaction affecting the bullet pull force.  A slightly dirty or dry lubricated neck may help. The carbon deposit left from firing is also a lube.

2. Also consider that your case neck tension my change over time after seating.  This will depend on brass hardness and the amount of case neck expansion when seating the bullet.

3. Powder moisture content.  Variations do occur and can affect the final MV.

4. Chronograph accuracy.  Light-activated chronographs are very handy, but are affected by lighting conditions and especially angle.]]> Reloading Methodology 223 https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2488 Re: Help me figure out what's going on. Changing ES and SD https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2290 Thu, 20 Apr 2023 07:58:10 +0000 If your chroni is closer than say about 9 ft you will never get true readings NEVER. ( likely the biggest cause of crazy readings - chroni too close and bad batteries)
If you shooting at different angles over chroni you also have numbers that jump about.
If you using cheap Chinese batteries or batteries of dubious consistency you can also experience some WTF moments.

I still believe the graphite will cause more issues than it will solve - usually crimping improves coated bullets consistency, but crimping comes with its own issues.

For now, make sure the chroni is up to task, then we can move forward. Do not use the coated bullets to test the chroni - you may just find a perfectly good chroni being held to blame for coated bullets behavior.]]> Reloading Methodology Treeman https://systemz.online/reloading-methodology/help-me-figure-out-whats-going-on-changing-es-and-sd/#post-2290