SD & ES

[Tikkat1x]

So, my first outing with my new magneto V3, did a test on 3 different rounds, im not really up on what the muzzle velocity should be, or what ES and SD even is, its something im obviously going to have to swat up on,
ill just show you my results and see what you think, good bad or ok,
all 223 loads.

Load1, hornady 55gr V-max, 20.4gr of RL-10, Min 2702, Max 2744, Av 2727, SD 11.6, ES 42, 10 shots.

load 2, Sierra 55gr SPT, 23.5gr of N-133, Min 3015, Max 3075, Av 3058, SD 17.6, ES 60, 10 shots

load 3, sierra 69gr TMK 24gr of N-140, Min 2744, Max 2782, Av 2763, SD13.7 ES 38, 10 shots.

 

[Brave Echo Niner]

ES - Extreme spread, this is the lowest value of the range, subtracted from the highest value, to show variation.
SD - Standard deviation, this is a mathematical measure of how tightly around the mean average the values of the data are, again a method of showing variation.

Ultimately with these figures you want them to be as low as possible. As the two are linked I would suggest focus on ES, it's easier conceptually and if the ES is good, the SD has to be good.


For myself, handloading for a competition, I'm always aiming for single digit ES on a 10 shot string, for stalking I'll accept up to 30FPS but ideally single digits.
For factory ammunition, from what I've seen an ES of 25 or below is good, 50+ is also not uncommon.

In relation to how quick the loads should be going that will depend on barrel length, true case capacity, COAL etc, so without knowing a lot more information they could be either really healthy speeds or quite sedate.


Hope this helps,

Ben

 

[Stalker62]

Lots of shite on the t'internet.

Lots of shite from the USA.

However.

I like this chap...

 

[Tikkat1x]

Lots of shite on the t'internet.

Lots of shite from the USA.

However.

I like this chap...

iv seen some of hid videos before, and with what he said about 50 FPS at 1000 yards, with my load there would be a 26" difference, thats a fair old miss not that i plan on doing any 1000 yard stuff,
i think at the distances ill be shooting i think its probably something i shouldn't worry myself to much with,

 

[Tikkat1x]

ES - Extreme spread, this is the lowest value of the range, subtracted from the highest value, to show variation.
SD - Standard deviation, this is a mathematical measure of how tightly around the mean average the values of the data are, again a method of showing variation.

Ultimately with these figures you want them to be as low as possible. As the two are linked I would suggest focus on ES, it's easier conceptually and if the ES is good, the SD has to be good.


For myself, handloading for a competition, I'm always aiming for single digit ES on a 10 shot string, for stalking I'll accept up to 30FPS but ideally single digits.
For factory ammunition, from what I've seen an ES of 25 or below is good, 50+ is also not uncommon.

In relation to how quick the loads should be going that will depend on barrel length, true case capacity, COAL etc, so without knowing a lot more information they could be either really healthy speeds or quite sedate.


Hope this helps,

Ben

Thanks Ben, very helpful yes, not sure how id go about changing the results as there now at the stage where there done to the best group size at 100 yards, thats brass, bullet weight and powder charge, and seating depths, surly a change in any of them would result in a poorer group size, but to be honest i think its all above my capability's for the time being, still learning and all that, at least now with some true muzzle velocities i can now set my ballistics calculator, i was working off the Hornady book before at 2800, not a lot of difference at fox ranges, but at 500 yards its a good 5",

 

[Brave Echo Niner]

Thanks Ben, very helpful yes, not sure how id go about changing the results as there now at the stage where there done to the best group size at 100 yards, thats brass, bullet weight and powder charge, and seating depths, surly a change in any of them would result in a poorer group size, but to be honest i think its all above my capability's for the time being, still learning and all that, at least now with some true muzzle velocities i can now set my ballistics calculator, i was working off the Hornady book before at 2800, not a lot of difference at fox ranges, but at 500 yards its a good 5",

Yep difficult if you’re already worked up the load - if it’s working for you though that’s the main thing.

Within standard foxing/stalking distances it doesn’t tend to come into play too much, but when you stretch the range that’s where you’ll start to see the effects of the shots vertically stringing.

 

[ColinBr]

Yep difficult if you’re already worked up the load - if it’s working for you though that’s the main thing.

Within standard foxing/stalking distances it doesn’t tend to come into play too much, but when you stretch the range that’s where you’ll start to see the effects of the shots vertically stringing.

Maybe better stating what your reloading kit and prep is like to try and consistently achieve single figure SDs

I have a funny feeling your kit will be a fair bit more than a standard press and scales.

For the guys who just want to have a fair plink, I think we need to realise the lengths people go to achieve this. That way they don't get to hung up by the figures.

 

[Brave Echo Niner]

Maybe better stating what your reloading kit and prep is like to try and consistently achieve single figure SDs

I have a funny feeling your kit will be a fair bit more than a standard press and scales.

For the guys who just want to have a fair plink, I think we need to realise the lengths people go to achieve this. That way they don't get to hung up by the figures.

Not wrong there.

I’m fortunate to have access to an AutoTrickler to get the powder charge very accurate (I only accept +/- 0.01 grain, which is a hair finer than the kernels of powder), and I’m anally retentive with case prep, primer pocket uniforming etc.

What I would say is sub 30 is mainly finding the velocity node in my experience, it’s getting from 20 down to single digits that the additional kit really helps with.

Ben

 

[ColinBr]

Not wrong there.

I’m fortunate to have access to an AutoTrickler to get the powder charge very accurate (I only accept +/- 0.01 grain, which is a hair finer than the kernels of powder), and I’m anally retentive with case prep, primer pocket uniforming etc.

What I would say is sub 30 is mainly finding the velocity node in my experience, it’s getting from 20 down to single digits that the additional kit really helps with.

Ben

It's exactly that.

People need to realise the time and expense needed to achieve this consistently, and to be honest they need to be competitive enough to see any real difference it would make to they're shooting.

I no longer compete (not that I ever have in fullbore) as I no longer have the drive needed to compete.
So I am happy so long as I can get a nice touching group and consistently hit targets at further ranges. In essence I have fun with it.

 

[Ronin]

If reloading for deer within normal killing ranges then es wouldn’t be a concern

Some loads can show great grouping with large es

Shooting at beyond 5-600 is where I’d be concerned about Es greater than 20 (personally)

If your shooting is primarily for deer then just enjoy what you have