Truth or fiction

[TTE]

Is this true or did my chrono have a brain f@rt

Did some 3 round load testing today.
Everything shot pretty well accuracy wise.

2 loads stood out as a bit better than the others

IMR 7828

1 - 3094 fps
2 -3100 fps
3 - 3094 fps
ES - 6
SD -3

VVN560
1 - 3143 fps
2 -3143 fps
3 -3143 fps
ES -0
SD - 0

Generally my ES is about 20 -30 and SD 18 or so

After shooting that rifle, I switched to a 35 Whelen and the numbers were back to where they had been previously, so I don't think it's the chrono.

If the chrono is correct, that is the lowest ES and SD I have ever seen in my loads. Anyone else (probably) run 0 ES and SD ? If many shooters have, maybe I'm finally getting the hang of this hand loading stuff after 35+ years

 

[6Creed73]

I never use ES/SD numbers for just 3 shots, I base my ES/SD numbers off 10 shot strings. With that said, I guess it's possible to get 3 rounds with the exact same velocity. But if I were you I'd take that load and shoot some 10 shot strings.

If the 3 shot results are any indication, it will still probably be good ES/SD...but highly unlikely they will be that low.

 

[Rocketvapor]

Which chrono?
I've had 3 "DUP" in a row with a ProChrony.
Likely due to instrumental resolution.

 

[DLT]

I have had 2 in a row with a magnetospeed. Never 3

 

[TTE]

Which chrono?

Oehler

 

[Chris Edmondson]

I've had 3 in a row with my Labradar, proof I guess, that anything can happen.

 

[SecondsCount]

I remember when I was testing RL16 in my 6X47L and the first 3 of 5 were identical. I almost thought the chrono was broken.

 

[chromatica]

With a sample size of 3 rounds, your SD number is meaningless. For statistical significance, you need to have a sample size of 20 shots. You might get a vague idea from a sample size of 10, but with 3 rounds you are just kidding yourself with both your ES and SD numbers.

 

[Homerange]

Yep, true !
Stumbled on a 130gr load for 308 with a book max load of ADI 2208 (Varget) with NO load development that gave me a ES of 6fps too. That it shot a 1/2 MOA group too was like I'd won the lottery.

 

[Straightshooter1]

Is this true or did my chrono have a brain f@rt

Did some 3 round load testing today.
Everything shot pretty well accuracy wise.

2 loads stood out as a bit better than the others

IMR 7828

1 - 3094 fps
2 -3100 fps
3 - 3094 fps
ES - 6
SD -3

VVN560
1 - 3143 fps
2 -3143 fps
3 -3143 fps
ES -0
SD - 0

Generally my ES is about 20 -30 and SD 18 or so

After shooting that rifle, I switched to a 35 Whelen and the numbers were back to where they had been previously, so I don't think it's the chrono.

If the chrono is correct, that is the lowest ES and SD I have ever seen in my loads. Anyone else (probably) run 0 ES and SD ? If many shooters have, maybe I'm finally getting the hang of this hand loading stuff after 35+ years

In a larger series of shots, more than once I've had 3 shots in a row that had the same velocity. So, 3 in a row can easily happen. I'll mention too that of those 3 shots having the same velocity in a row, the POI's were never in the identical hole.

But, yes . . . that's a good indication that your hand loading is you're "getting the hand of this loading stuff", especially when you're typically getting SD's like 18.

 

[762plinker]

i have..rare but it happens.

With a sample size of 3 rounds, your SD number is meaningless. For statistical significance, you need to have a sample size of 20 shots. You might get a vague idea from a sample size of 10, but with 3 rounds you are just kidding yourself with both your ES and SD numbers.

wrong you need a sample size of 1000-10000. it is just a feel good number for shooters. it is scientifically insignificant with our sample sizes

 

[Webster]

Is this true or did my chrono have a brain f@rt

Did some 3 round load testing today.
Everything shot pretty well accuracy wise.

2 loads stood out as a bit better than the others

IMR 7828

1 - 3094 fps
2 -3100 fps
3 - 3094 fps
ES - 6
SD -3

VVN560
1 - 3143 fps
2 -3143 fps
3 -3143 fps
ES -0
SD - 0

Generally my ES is about 20 -30 and SD 18 or so

After shooting that rifle, I switched to a 35 Whelen and the numbers were back to where they had been previously, so I don't think it's the chrono.

If the chrono is correct, that is the lowest ES and SD I have ever seen in my loads. Anyone else (probably) run 0 ES and SD ? If many shooters have, maybe I'm finally getting the hang of this hand loading stuff after 35+ years

My chony gives goofy numbers when a bright sun is at an angle under the sun screens. About 1-3PM. When the chono wasn't giving good numbers they didn;t make sense (a big spread FPS or a miss). Never had close numbers that were suspicious. If you are not shooting competition and the groups are small I wouldn't worry about it. Try some shots on a cloudy day or when the sun dousn't reflect off the bullet (morning or late afternoon. That should tell you if the chony numbers are real. Hard to believe those small numbers. I get 15-20 ES with accurate loads with my Varmint hunting 6BR.

 

[Homerange]

My chony gives goofy numbers when a bright sun is at an angle under the sun screens. About 1-3PM. When the chono wasn't giving good numbers they didn;t make sense (a big spread or a miss). Never had close numbers that were suspicious. If you are not shooting competition and the groups are small I wouldn't worry about it. Try some shots on a cloudy day or when the sun dousn't reflect off the bullet (morning or late afternoon. That should tell you if the chony numbers are real. Hard to believe those small numbers. I get 15-20 ES with accurate loads with my Varmint hunting 6BRR.

Never questioned mine but its previous owner did.
He contacted its supplier voicing concern and got another exact same model to check it against. I witnessed 2 folding Crony's placed as near to each other and shots fired over both at once.
The difference was never more than a digit or 2 and they were within 5fps of one another.

Sure, if you were a pessimist you'd need 3 to better ensure none were lying to you.

Then before he could return the Chrony lent to him for checks the shop owner passed and he all of a sudden had 2 Chrony's....the older unit given to me as thanks for the use of our range.

 

[TTE]

My chony gives goofy numbers when a bright sun is at an angle under the sun screens. About 1-3PM.

Tough for me then .... I live in Florida

 

[Shooter13]

Tough for me then .... I live in Florida

Don't worry about that! Between 1-3 every fay it rains! 15 minutes and 2 minutes later it's dry and more humid!

 

[SKWERLZ]

I remember when I was testing RL16 in my 6X47L and the first 3 of 5 were identical. I almost thought the chrono was broken.

My old 260 had awesome ES’s with R16

 

[Mark W]

Don't worry about that! Between 1-3 every fay it rains! 15 minutes and 2 minutes later it's dry and more humid!

I always said that I could be a summertime weather man in central Florida. “Sunny with highs in the low to mid 90s and a chance of afternoon thunderstorms, some possibly severe”. It’s literally the same forecast all summer…..lol

 

[Shooter13]

I've had 3 in a 10 string but not sure 3 in a row, close within a foot or 2

 

[Shooter13]

I always said that I could be a summertime weather man in central Florida. “Sunny with highs in the low to mid 90s and a chance of afternoon thunderstorms, some possibly severe”. It’s literally the same forecast all summer…..lol

Yep! I worked from Tampa Bay to Miami in 2018 and 19

 

[kenhwind]

I always said that I could be a summertime weather man in central Florida. “Sunny with highs in the low to mid 90s and a chance of afternoon thunderstorms, some possibly severe”. It’s literally the same forecast all summer…..lol

Not quite the same forecast we do have an occasion hurricane or two.
Well, if you're a beer and wing person Hurricanes could be a weekly ordeal.