es/sd standards

[R Reed]

So I have never been able to get a straight answer on this question. I have heard everything from single digits, to it does not matter. For those that do care about it, I can never seems to get a straight answer as to what they consider to be acceptable, what is bad, or what their target goal it.

While watching this video today, the creator stated that match ammo is supposed to have a SD of 15 or less. Right around the 6min mark.

https://www.youtube.com/watch?v=LsK2i1aMpVE

Is this correct? What are your target goals or what do you consider acceptable/unacceptable if your willing to share. are there any official military standards?

I also found this article stating match ammo is typically 10-15 or less, and standard ammo is 20-40.
https://trueshotammo.com/academy/wh...ery,precision, especially at extended ranges.

 

[Walkalong]

What application?

Up close it's not real important, especially for handguns (You didn't say rifle, handgun, or both). Long distance? It's very important, because it will show
up as vertical dispersion much taller than the group is wide, assuming a good shooting load up close and steady wind or good wind reading.

 

[Blue68f100]

It depends on the distance your shooting. The longer the range the lower you want the numbers. I shoot for under 10 on my match ammo.

 

[R Reed]

What application?

Up close it's not real important, especially for handguns (You didn't say rifle, handgun, or both). Long distance? It's very important, because it will show
up as vertical dispersion much taller than the group is wide, assuming a good shooting load up close and steady wind or good wind reading.

In relation to rifle.

Application.... I am looking for a more generalized answer, perhaps to understand in what applications it is important and which it is not and what the boundaries are regardless if they are applicable to my specific application. I feel like giving my application will give me responses that are too tailored and limit my understanding of the subject. With that said I feel like there needs to be some basic framework, but please feel free to answer based on your applications as well. I am just a regular shooter, no competition as of yet, maybe some day for fun. I like shooting small groups, and I like shooting long distance, which I do not get to do nearly as often as I would like seeing that the closest range I have over 100yds is a 2hr drive each way. For me small groups is a consistent 1moa 10 shot group. I would like to get down to 1/2 moa all day.

Distance, to me, I generally break distances down as 100yds, 250yds, 500yds, 750yds, 1000yds, and ELR as anything beyond 1000 (looking at you Mark and Sam after work). I personally consider anything over 500yds long range. That is not set in stone, that Is just how my brain breaks ranges down. I am more than open to learning a better way.

 

[MEHavey]

Figure ½ of 1% of the velocity is a superb SD for long-range rife work
Three times that for a handgun -- or shorter (100-200 yd) is fine for rifle.

 

[AJC1]

Guys use measures and drop powder for 200 yard br.... the target rules the day. The size of your target matters. In varmit metallic Silhouette things are very small so vertical and horizontal matters. The targets seem bigger in prs but you have all the complications of position shooting. When you get to 600 it's starts to make a big impact on your score and further it just gets worse. With a pistol most say it doesn't matter, and I tend to agree, what about pistol caliber carbines with the rams at 200.....

 

[Laphroaig]

Whatever number that you are looking for, be sure to shoot enough shots to get a representative accounting of what to expect. 3 or 5 isn't enough.

 

[R Reed]

Whatever number that you are looking for, be sure to shoot enough shots to get a representative accounting of what to expect. 3 or 5 isn't enough.

I typically shoot no less than 10, now with my garmin, I will be able to collect data while i shoot groups so that sample size will go way up.

 

[GeoDudeFlorida]

Application absolutely matters. If you’re taking one shot and need that bullet to hit inside a 4-6” span in order to get a chance at a clean kill, then ES only matters shot-to-shot under identical conditions: a cold barrel, clean or dirty, identical atmospheric conditions, shooting angle, distance, etc. There are no fouling shots in the woods.

Depending on what you’re hunting the numbers might matter a lot or none at all.

Shooting paper and filling in spreadsheets is a totally different game. Again, the reason you get specific answers is because it really depends on a whole bunch of variables.

 

[R Reed]

Application absolutely matters. If you’re taking one shot and need that bullet to hit inside a 4-6” span in order to get a chance at a clean kill, then ES only matters shot-to-shot under identical conditions: a cold barrel, clean or dirty, identical atmospheric conditions, shooting angle, distance, etc. There are no fouling shots in the woods.

Depending on what you’re hunting the numbers might matter a lot or none at all.

Shooting paper and filling in spreadsheets is a totally different game. Again, the reason you get specific answers is because it really depends on a whole bunch of variables.

Part of what I would like to understand is what variables make es/sd important or irrelevant. I can't get that answered based on my specific criteria/ use case.

Your criteria seem to be paper and hunting. If that's correct, at what distances to you consider es/sd to be a critical factor, at what distances do you consider them negligible? Do you have set standards or goals for es/sd? If so under what criteria?

 

[GeoDudeFlorida]

Part of what I would like to understand is what variables make es/sd important or irrelevant. I can't get that answered based on my specific criteria/ use case.

Your criteria seem to be paper and hunting. If that's correct, at what distances to you consider es/sd to be a critical factor, at what distances do you consider them negligible? Do you have set standards for es/sd and for which variables?

I’m shooting softball size targets at rock throwing ranges. The only number I’m looking at is velocity inside of 50-75yds. As long as I’ve got enough velocity for a thru and thru on a 100lb boar hog, I’m good.

 

[Laphroaig]

Shooting paper and filling in spreadsheets is a totally different game.

The Garmin has given us the ability to easily create statistics. It's all good data and I suppose you can infer that low numbers mean that it's a better load. But other than that I think we give it more attention than it deserves.

It's kind of like a borescope; it gives us a reason to doubt something that has worked well for us for many years. Probably best not to know for most of us. Long range guys have a pretty valid application, otherwise...

 

[fxvr5]

Don't overthink it. I see way too many poeple trying to make sense of a sd of 10 versus a sd of 15. It's time wasted. You can play the numbers game all day. But, do they mean anything other than one number is bigger/smaller than the other? If the load shoots the smallest group, it doesn't matter what the es/sd is, big or small. Your target will tell you what's best, not the chronograph.

 

[R Reed]

I’m shooting softball size targets at rock throwing ranges. The only number I’m looking at is velocity inside of 50-75yds. As long as I’ve got enough velocity for a thru and thru on a 100lb boar hog, I’m good.

And that's a great answer, for you it does not matter at 75yds or less.

 

[Blue68f100]

If you want to see how the variation in velocity impacts you at distance. Run the numbers through a drop calculator. Then compare the difference in elevation drop at distance. the max distance I can shoot at my home range is 300 yrds. It has a little impact but nothing like shooting at 600+. Also remember if you happen to be in time with the harmonics in the barrel it can self adj the elevation to a point. I've seen some terrible number shoot good and good number shoot bad. Wind is your biggest hindrance when it comes to shooting long distances.

 

[Chuck R.]

If you want to see how the variation in velocity impacts you at distance. Run the numbers through a drop calculator. Then compare the difference in elevation drop at distance. the max distance I can shoot at my home range is 300 yrds. It has a little impact but nothing like shooting at 600+. Also remember if you happen to be in time with the harmonics in the barrel it can self adj the elevation to a point. I've seen some terrible number shoot good and good number shoot bad. Wind is your biggest hindrance when it comes to shooting long distances.

It is a great way to demonstrate the effect.

As some of the others said, it comes down to task & purpose. Long range rifles I want single digit SDs, woods carbines I don't care. I haven't yet found a case with my long range rifles that I couldn't have both accuracy and good stats, so it's not like they're mutually exclusive.

 

[R Reed]

It is a great way to demonstrate the effect.

As some of the others said, it comes down to task & purpose. Long range rifles I want single digit SDs, woods carbines I don't care. I haven't yet found a case with my long range rifles that I couldn't have both accuracy and good stats, so it's not like they're mutually exclusive.

I also don't feel they are exclusive. I typically find a good es/sd, then tune seating depth for accuracy/harmonics. So far it has worked every time.

I have run the numbers a couple times through a ballistic calculator with data from my load workups. Comparing a sd of 10 and 45 i found a difference of 0.3moa, 0.1 vs 0.4 moa.

 

[AJC1]

I also don't feel they are exclusive. I typically find a good es/sd, then tune seating depth for accuracy/harmonics. So far it has worked every time.

I have run the numbers a couple times through a ballistic calculator with data from my load workups. Comparing a sd of 10 and 45 i found a difference of 0.3moa, 0.1 vs 0.4 moa.

In your example you have loaded up a box of ammo to go hunt the Midwestern planes. Your load has an SD of 25 and you punch the shot into your calculator dial your scope and take the shot on an anilope at 500 yards. Do you connect for a clean kill, wound the animal or clean miss...

 

[Toprudder]

As far as SD/ES not being important at closer distances, that is true up to a point. I’m normally not too concerned about pistol loads that I know I will never be shooting past 25 yards, but I use the SD/ES as a measure of how “happy” the component combination is. For instance, if I see a large ES in a 357mag load, I may do a little more investigation, such as a powder-forward test. I found one combination that had over 80fps ES, but when I did a powder-forward test, I saw 300fps difference. Would it make much difference on a 25 yard target - maybe not, but I will look for a more consistent combination.

 

[GeoDudeFlorida]

As far as SD/ES not being important at closer distances, that is true up to a point. I’m normally not too concerned about pistol loads that I know I will never be shooting past 25 yards, but I use the SD/ES as a measure of how “happy” the component combination is. For instance, if I see a large ES in a 357mag load, I may do a little more investigation, such as a powder-forward test. I found one combination that had over 80fps ES, but when I did a powder-forward test, I saw 300fps difference. Would it make much difference on a 25 yard target - maybe not, but I will look for a more consistent combination.

And that’s exactly what I was trying to get across: I will see signs of inconsistency in the load without having to run any numbers. Powder forward/back is one of the first things I test - after checking neck scorching, primer reseating, powder residue (case, chamber, barrel and bench), and POA vs. POI. I can tell in two shots whether or not the components are in their “happy place.”

That goes for rifles and handguns. Lever guns in particular I’m a whole lot more concerned with how the feed ramp and lifter are treating the cartridge than with how “the numbers” look. If you’re using chronograph readings and statistical analysis to find out if your cartridge is being set-back in the feed operation, you’ll probably end up with a kaboom sooner rather than later.

A good load hits where you aim first shot and every shot after up to the point that shooter fatigue and a hot barrel become the overriding factors of accuracy.

Just my opinion on the subject as a general purpose firearm user. I’m highly fallible and the above comments are subject to interpretation.

 

[R Reed]

And that’s exactly what I was trying to get across: I will see signs of inconsistency in the load without having to run any numbers. Powder forward/back is one of the first things I test - after checking neck scorching, primer reseating, powder residue (case, chamber, barrel and bench), and POA vs. POI. I can tell in two shots whether or not the components are in their “happy place.”

That goes for rifles and handguns. Lever guns in particular I’m a whole lot more concerned with how the feed ramp and lifter are treating the cartridge than with how “the numbers” look. If you’re using chronograph readings and statistical analysis to find out if your cartridge is being set-back in the feed operation, you’ll probably end up with a kaboom sooner rather than later.

A good load hits where you aim first shot and every shot after up to the point that shooter fatigue and a hot barrel become the overriding factors of accuracy.

Just my opinion on the subject as a general purpose firearm user. I’m highly fallible and the above comments are subject to interpretation.

I'm not so much concerned at to what factors create or effect ES/SD, simply under what conditions ES/SD are a relevant factor, and what tolerances need to be held in those circumstances.

 

[gwpercle]

I go by accuracy , if the load shoots one hole groups ... I don't care what the
ES SD or OCD is ... it doesn't matter .
An accurate load is an accurate load ... Choot it !
Gary

 

[Varminterror]

the creator stated that match ammo is supposed to have a SD of 15 or less. Right around the 6min mark.

https://www.youtube.com/watch?v=LsK2i1aMpVE

Is this correct?

No.

1) There is no universal standard which states any parameter for SD would qualify as “match ammo.”

2) For any and all of my match ammo I make, 15SD would be considered a gross failure, especially for only 5shot strings.

I shared all of my match ammo data from last season for my ELR rifle in this thread:

Chronograph results and statistical analysis

Only ONE match out of last season broke double digit SD over a 30 round match string, which was a 11SD, which was an odd up-trending match day. Multiple weekends tallied single digit SD for 60-74 rounds in the string. For 5-10 shot strings, my SD typically hangs 4-7 fps.

Of course, that isn’t just a qualification for “match” ammo, I get the same results for most of my rifle loads. Gas guns are less consistent in ignition, but I still wouldn’t sleep on a 15SD for only 5 shots.

Here’s an example of when SD is pertinent - rather, consistent velocity is pertinent. This is a pair of groups (really 3 groups) I shot side by side one afternoon at 875 yards on a pair of 66% IPSC’s. One is a 6.5 Grendel with factory match ammo with 78fps ES over 15 rounds, Orange rectangle, whereas the two green ovals are 3 shots followed by dialing up .2mrad and 12 more shots with a 6 creed with only 24fps ES in these 15 shots. Note that the groups are holding ~1moa for windage, which was rather gusty that day, ~15mph right to left, but there’s about the same 8-9” windage in the group, but the load with more consistent velocity prints a stripe along the waterline, whereas the less consistent load scatters up and down the plate, roughly 3x more elevation dispersion in the more variable ammo. Either of these loads would print ~1/2”-3/4” at 100yrds, but putting a little more air under them reveals the influence that inconsistent velocity has.

 

[GeoDudeFlorida]

I go by accuracy , if the load shoots one hole groups ... I don't care what the
ES SD or OCD is ... it doesn't matter .
An accurate load is an accurate load ... Choot it !
Gary

This exactly!

I'm not so much concerned at to what factors create or effect ES/SD, simply under what conditions ES/SD are a relevant factor, and what tolerances need to be held in those circumstances.

Okay. I guess I just don’t get the question, then. If you’re looking for a Universal Y.y +/- X% or something like that then I don’t think it exists. It’s an individual metric according to operations, equipment and goals. Shooting fatigue sets in a lot quicker for me these days than 30 years ago so whatever standard I might have observed then is deprecated now.

Anyway, good luck and maybe someone else has the Answers.

 

[R Reed]

This exactly!

Okay. I guess I just don’t get the question, then. If you’re looking for a Universal Y.y +/- X% or something like that then I don’t think it exists. It’s an individual metric according to operations, equipment and goals. Shooting fatigue sets in a lot quicker for me these days than 30 years ago so whatever standard I might have observed then is deprecated now.

Anyway, good luck and maybe someone else has the Answers.

There is no universal metric. Yes, it is based on a set of factors/variables. I am trying to figure out what the variable are, or where ED/sd are a critical factor. kinds of like a flow chart, at x yards, for y application, a SD of z or better is needed.