When does one need a crono?

I am confused about using a chrono for load development,
Myself when to purchase a chrono, was once my load was developed, to know it's velocity to create adequate drop charts or input info in a ballistic app.
Or in IPSC to know my PF.

And going back to load development, did it without a chrono, I looked for all other pressure signs.
Works out my best load was 42.7gr of Varget load behind a 175SMK bullet,and is doing exactly 2700fps (chronied it 1-2 months later after all load testing was done).
What confuses me is what follows : People all tell me to use ES and SD to find a good load, I have found 3 accurate nodes and 42.7gr was my most accurate, I can shoot 10 shot groups at 300M under 1/4moa vertical, and it's my load with the worst ES and SD out of my 3 accurate recipies, and... my ES/SD is considered to be too much by many as I load developed blindly, but this load simply works, repeatable and really works...
 
'Boo said:
Go to the page linked above by leveractionjunkie to see what John Barsness opinion is on standard deviation.

Like others have mentioned John B is one of the few gun writers whose opinion I respect.
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Thanks that was an excellent read.
Maybe I like it so much since it supports my actual situation!
Went downstairs to check some data I had written and targets I had kept.

Mind you, that I never shoot under 5 rounds for a group, and will often do 10 round groups.
My best target is a sub 1/2 moa group, 10 shots, 300M, 1/4 moa vertical, and I had labradar next to rifle for that target.
SD = 12.5 and ES = 23

Last year, after having found my load prior and bought a chronograph afterwards, that's when I started hearing people around giving me the magic numbers, which we're somewhere around single digit for SD and under 15 for ES.
I then temporarily worked on obtaining these numbers, and quickly quit since my sub 1/2 moa ammo would now perform sub moa, but on the chronograph it was perfect.

I will quote the article and remember this from now on when SD numbers are spoken of : ''After three or four years of using this Chrony, I’ve found about the same correlation between standard deviation and accuracy as between asphalt and trout.''
 
MartyK2500 said:
Thanks that was an excellent read.
Maybe I like it so much since it supports my actual situation!
Went downstairs to check some data I had written and targets I had kept.

Mind you, that I never shoot under 5 rounds for a group, and will often do 10 round groups.
My best target is a sub 1/2 moa group, 10 shots, 300M, 1/4 moa vertical, and I had labradar next to rifle for that target.
SD = 12.5 and ES = 23

Last year, after having found my load prior and bought a chronograph afterwards, that's when I started hearing people around giving me the magic numbers, which we're somewhere around single digit for SD and under 15 for ES.
I then temporarily worked on obtaining these numbers, and quickly quit since my sub 1/2 moa ammo would now perform sub moa, but on the chronograph it was perfect.

I will quote the article and remember this from now on when SD numbers are spoken of : ''After three or four years of using this Chrony, I’ve found about the same correlation between standard deviation and accuracy as between asphalt and trout.''
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Just like how you don't shoot under 5 round groups because the sample is too small your experience does not count as conclusive proof.

Also, at 300M your SD of 12 and ES of 23 probably would not show up on paper.

There are top notch shooters on both sides of the debate but considering 2 time PRS series champion does his load dev at 100M I think it is good enough for me.

To the OP. You don't need a chrony but I think they can help depending on your goals.
 
If your just working up a load to shoot decent group to hunt with it may not be something you need. For those that are a bit more serious or compete (all those whom shoot on Provincial & National teams where I shoot use the LabRadar. They used the Magnetospeed but found it wasn't consistent enough) you shouldn't be without one. I'm on my second Shooting Chrony. Shot the first one, blowed it up real good! I bought it because I had purchased a 450 Rigby. There was very little loading data for it. I was given loads from Game Wardens & PH's in Africa that shoot the 450 Rigby. The challenge was they used Somchem powder. I had an idea what velocity's to be at with various bullets weights, but had to work up loads using powder that was available in North America. It as become an invaluable tool. I use it for all load development. You start to see patterns after a while when working up loads.
 
Ryan.M.Anderson said:
Just like how you don't shoot under 5 round groups because the sample is too small your experience does not count as conclusive proof.

Also, at 300M your SD of 12 and ES of 23 probably would not show up on paper.

There are top notch shooters on both sides of the debate but considering 2 time PRS series champion does his load dev at 100M I think it is good enough for me.

To the OP. You don't need a chrony but I think they can help depending on your goals.
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No matter how many thousand rounds i have shot, my experience will never be relevant unless i win big matches, that’s a fact as i tend to listen to national winners much more than the guy who thinks he has got the recipe.

In my personal experience, and for having shot that ammo up to 900M, i do believe in the SD is not important theory.
I anneal every firing, neck size, bump shoulders and turn every firing, powder with fx120 and tweezers to the gn close.
I can get numbers real low if i want, but my record groups, which are 10 shot groups (more than 5 even) are with my ugliest SD/ES loads.
Using labradar so measurements have got to be well read.

By not having won any matches, i fully understand this has no real weight still, as i do the same the other way around.
 
anyone that reloads needs a chrono, or at least access to one. You have no idea what your loads mean and if the minimum you're loading to is even safe. Not all brass is the same, and powder burn rates can change dramatically from lot to lot. Checking for pressure signs is obviously helpful, but checking velocity can tell you a ton about what you are getting.
 
MartyK2500 said:
I can get numbers real low if i want, but my record groups, which are 10 shot groups (more than 5 even) are with my ugliest SD/ES loads.
Using labradar so measurements have got to be well read.
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consistent SD on a scatter node will shoot poor. Sloppier SD that slides of each side of an optimal node will shoot well. Vertical can start to suffer at long range
 
todbartell said:
consistent SD on a scatter node will shoot poor. Sloppier SD that slides of each side of an optimal node will shoot well. Vertical can start to suffer at long range
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I still find it amusing when some people try to develop loads, based on ES. and SD, and then they are shocked when a load with lower numbers, does not shoot as well as a load with higher numbers.
 
i once felt an urge to buy one, but it passed. I lug too much crap to the range as it is, and I also use shooting as a low or different tech counterpoint to my job, which is IT. I have no desire to bring anything electronic into my shooting world.

You don't "need" one, or at least not at this point. There are more important skills and good habits for early reloaders to develop before chasing numbers becomes the dominant part of it.
 
Mark-II said:
i once felt an urge to buy one, but it passed. I lug too much crap to the range as it is, and I also use shooting as a low or different tech counterpoint to my job, which is IT. I have no desire to bring anything electronic into my shooting world.

You don't "need" one, or at least not at this point. There are more important skills and good habits for early reloaders to develop before chasing numbers becomes the dominant part of it.
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We could say, if you shoot competitively, be it pistol or rifle, you definitely need one.
I ran a few years without one on pistol and did just fine leaching off other peoples chronographs.

Todbartell : I would like very much to learn more about these scatter nodes and why my good results seem to be tied to bad SD/ES, is there any internet reading material you could suggest?
As I would like to try to load develop the chronograph way for sakes of experimentation. I know my 42.7gn load is constant sub 1/2 moa, even in 10 shot groups at a distance, but if I could find a way to get sub 1/3 moa i'd be even happier.
 
Aside from pressure testing equipment, MV is your best measure of pressure. If you never stray from published load data, you could probably get away without one, but when you're ready to develop your own loads, one will be indespensible.
 
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Ganderite said:
Reloading without a Chrony is like driving without a speedometer - or flying without an altimeter. It can be done, but you are missing important information.
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At what point do you start to use a chrony? When doing initial load development when looking for accuracy nodes? Or once a node is found, then use a chronograph to see what the velocities are at and find the most consistent velocity load?

I had been doing the latter, once I find a load that is accurate, use the chronograph to determine the velocity and make my dope charts off that information. I had not been using the chronograph information for anything else.
 
TrevorJ said:
At what point do you start to use a chrony? When doing initial load development when looking for accuracy nodes? Or once a node is found, then use a chronograph to see what the velocities are at and find the most consistent velocity load?

I had been doing the latter, once I find a load that is accurate, use the chronograph to determine the velocity and make my dope charts off that information. I had not been using the chronograph information for anything else.
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I usually load for accuracy. So I need a load that is accurate and a load near max pressure/velocity (for wind bucking).

I used to have a favorite load. After I bought a Chrony I discovered it was 175 fps slower that what I should have been using.
 
TrevorJ said:
At what point do you start to use a chrony? When doing initial load development when looking for accuracy nodes? Or once a node is found, then use a chronograph to see what the velocities are at and find the most consistent velocity load?

I had been doing the latter, once I find a load that is accurate, use the chronograph to determine the velocity and make my dope charts off that information. I had not been using the chronograph information for anything else.
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I chronograph from start to finish. Hence why I wish labradar would read all calibers and speeds, also why the magnetospeed is attractive to me. Ideally I’d chronograph every range session just because I like data.

When working up a load I select components and a look up my expected velocity from manual and possibly adjust for differences in my barrel length vs lab/manuals barrel length. Load up three rounds per charge between max and 10% below max. Charge weight increases vary based on case capacity. I then fire over Chrony at target and record velocities and note groups. Generally as loads approach max listed velocities groups begin to shrink and it say max and 1/2gr below max look nice then I’ll load up more of both charges. If it’s a varmint round I’ll do 15 of each charge and if it’s hunting rifle I’ll do 9. Then I have 3 groups of each charge to see if accuracy and velocity are consistent or not. Take the one closest to max book velocity and best accuracy and practice and then hunt.

Generally this has yielded good results for me and has gotten a load squared away without too much trouble. Obviously if the intent of the load is different ie to make a reduced load or something else then max velocity isn’t the goal but I still chronograph in order to find the target velocity.
 
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