Range Report Group size means little

[Dthomas3523]

But that's not my point. In some cases, first shots were factory, subsequent reloads using same components, but reloaded. My point in posting is in response to this notion that "the argument of higher accuracy and precision falls a bit flat these days."



I had already broken in the barrel in both cases. In my friend's case, the seating depth was well past barrel break in, as he had already done powder charge load development.



Perhaps I am completely taking the statement: "the argument of higher accuracy and precision falls a bit flat these days" completely out of context.

When people mention factory being as good as handloads, I take that as far as PRS it shooting 2moa or larger steel. I don’t care if I’m 1 holing that target when shooting practical size.

With the exception of smaller targets on kyl racks, I seriously doubt anyone can show an appreciable difference in score/impacts with this type of shooting. If they can, then everyone better hope guys like Phil Velayo don’t stop using factory ammo.

Sure you can say “well my .5 handload vs a 1moa factory load gives me .5 moa more to play with in my wobble and wind budget.”

But how many are missing a large amount of targets by .5moa or less?

There could actually be an argument that handloading may hurt the beginner to mid pack shooters. If they get their load dialed in enough to not miss that plate when they would have with factory ammo, they may not spend the time to get batter at making center punch calls.

 

[morganlamprecht]

6br lapua factory ammo is cloverleaf stuff

see someone reload 6br, just volume/throwing powder and it makes factory look like a shotgun

actually see someone shoot true 300 or 600 yard BR loads with proper loading... and youll cry

everybody's a big fish in their pond

thats kind of always been my thought...

if you arent doing what the BR guys are doing...from prep, to perfect rifles, rifle management, flags, changing loads at the bench, etc etc...

if you arent shooting a full rigged f class gun with all the prep, etc etc of the f class guys...

how are you going to validate or prove out to that level?

if the "load" is all that matters...and not the completely different styles and levels of equipment...someone in the f class and BR game needs to pull up with bipod and a squeeze bag....no excuses, if the load is perfect...

EDIT: not "you" as in you personally, just "you" as in whoever the shooter is

 

[morganlamprecht]

When people mention factory being as good as handloads, I take that as far as PRS it shooting 2moa or larger steel. I don’t care if I’m 1 holing that target when shooting practical size.

With the exception of smaller targets on kyl racks, I seriously doubt anyone can show an appreciable difference in score/impacts with this type of shooting. If they can, then everyone better hope guys like Phil Velayo don’t stop using factory ammo.

Sure you can say “well my .5 handload vs a 1moa factory load gives me .5 moa more to play with in my wobble and wind budget.”

But how many are missing a large amount of targets by .5moa or less?

There could actually be an argument that handloading may hurt the beginner to mid pack shooters. If they get their load dialed in enough to not miss that plate when they would have with factory ammo, they may not spend the time to get batter at making center punch calls.

Tate's maybe ran factory ammo more than anyone consistently at the top...aint many would wanna put their money against him

 

[Dthomas3523]

Tate's maybe ran factory ammo more than anyone consistently at the top...aint many would wanna put their money against him

Yep. He says he hasn’t measured a chamber in 6 barrels. Same exact 6br (whatever variant, I think ackley) load he worked up for the first barrel.

If that doesn’t tell a story, nothing will.

 

[morganlamprecht]

yup...

 

[LA260]

Perfect. Exactly what I wanted to read with a new 6.5x47 barrel on the way. 37.3Varget/140hybrids/0.050" off it is!

 

[2aBaC̶a̶]

I'm not even sure about the "shoot a lot" thing. It's a money pit as bad or worse than any other hobby out there. Of course, when I tell my wife about it, I say something to the effect of:

"If I buy the ammo, it costs $2/round. When I reload, I get to reuse the brass, the powder only costs about a quarter, and the bullet is about thirty cents."

Yeah well also depends if you're buying all the crazy gadgets to reload, you'll have to shoot alot more to pay for it in per shot savings.

I'm a frugal reloader.

I shot a 120 rounds of 300PRC the other day. That would have been $300 in retail ammo. it only took $150 for a new caliber and at $1 per round, I'm already in the green.

At 1000rds I will have saved close to $1000

 

[kthomas]

Reloading can be as simple or as difficult as you want to make it. It can be difficult to jump that initial hurdle as their seems to be a lot of "voodoo" in it, and no one can seem to agree on the best process. Sometimes it seems that the only thing 3 reloaders will agree on is that the other guy is doing it wrong.

Reloading is very time consuming, and if you account for the time, there's no way it's cheaper then factory ammo, especially as factory ammo gets better and cheaper as the months and years go on.

If you see yourself enjoying it as a hobby, or want to shoot a more "exotic" cartridge, or for whatever reason demand very exacting results from your ammo, then reloading is worth the jump. Otherwise, nothing wrong at all with sticking with factory ammo.

 

[morganlamprecht]

i think learning a sound/consistent/successful process is key for most starting off

there are some things guys unknowingly do that can cause a ton of issues...ive seen em happen in matches over and over...rounds not chambering, misfires, case head separations, etc....if thats happening, how snapped up is their charge and jump test work in reality?

 

[Rocketmandb]

i think learning a sound/consistent/successful process is key for most starting off

This is a 100% true statement. When I help new reloaders, I always tell them to start with a few, key elements. Get those right first, get comfortable, then add in additional elements one at a time.

 

[kthomas]

i think learning a sound/consistent/successful process is key for most starting off

theres some things guys unknowingly do that can cause a ton of issues...ive seen em happen in matches over and over...rounds not chambering, misfires, case head separations, etc....if thats happening, how snapped up is their charge and jump test work in reality?

The single best thing a new reloader can do is find a mentor that can start them off and help them along the way as questions and issues arise.

I was lucky to have two team Applied Ballistics ELR shooters as my mentors, whom I still reach out to if I experience anything weird.

If you don't have a decent sized precision rifle community in your area, finding the appropriate mentor may be difficult.

 

[Racer88]

If your idea of "practical shooting" is going out a couple or few hundred yards, then sure. But you don't need to be a benchrest shooter to get a lot of value out of reloading properly.

Example #1:

When I first got my 6CM, I did not have my dies yet, so bought 200 rounds of Hornady factory, match-grade ammo to break in the barrel and have a little fun. I was not overly impressed with the results. I was getting somewhere in the neighborhood of 3/4 MOA with 5-shot groups.

When I got my dies, I used the spent Hornady brass and was shooting 2" groups at 300 yards. Decent, but still short of where I wanted to be.

Finally, Lapua got into the 6CM game, and I bought a bunch of their brass. On my first trip to the nearby 100 yard range to get some once-fired brass, I fired the first shot, then the second. Where did it go? I had to look through the spotting scope to see that it went in the same hole. The rest of the shots were within .4 inches - and the rifle consistently shot in that neighborhood there on out.

Example #2:
First shots, post barrel break-in, out of my 300 PRC were using Hornady and I got 5-shot groups again in the 3/4 MOA range. My goal was to use this rifle for mile+ shooting. Without going into the gory details about my brass saga, I got better brass, found the load, and now shoot best groups roughly in the 1/3 range.

Example #3:
A friend was having issues with his newly rebarreled 338. He had his seating depth way out and was getting 3" groups at 300 yards. Brought the seating depth in, and his ES/SD dropped, along with his group size (roughly averages just over 1" now)

I'd love for someone who thinks that the "argument of higher accuracy and precision falls a bit flat these days" to explain what the reason could possibly be for these improving results using their logic and view of the reloading world.

This notion that you can consistently get the same results from factory ammo as you do from a post-load-development round is simply not supported by the data. CAN you get similar results? Sure, if all the stars align and it just so happens that your rifle is a good match for a particular factory ammo. WILL you always get similar results? No.

All good. I'm not arguing that factory match ammo is as good as hand-loads. But, unless one is REALLY going for tiny groups... to borrow from my own field.. "Is the difference clinically significant?"

I really get the "OCD" aspect mentioned earlier. I can totally identify with that! LOL! I'm pretty happy with getting 3/4-MOA without hardly trying.... and 1/2-MOA if I really try. My standards may evolve in the future. I may eventually get into loading my own. But, I think I've heard many old-timers with experience from the past say that today's factory match grade ammo is way better than it used to be.

While I've been to a few F-class matches, I really have no interest in becoming a "competitive" F-class shooter. I just like shooting at the longer distances, and those opportunities are few and far between in my area (literally). There are very few outdoor ranges in my area. To go beyond 300 yards, I have to drive for hours. It's a whole day evolution. The F-class events are a 2-1/2 hour drive away. But, it's the closest 600 yard range, and the only other way I'd have access to that range is by joining the club.

 

[MCHOG]

If you say took a shot marker system and shot 5 shots. Then replace the paper and shoot 5 more shots.

Do this for about ~30 shots, you would get what is closer to the real group size.

And, in fact, 30 is the number that is generally regarded in the scientific world as a minimum statistically significant sample size.

 

[Greg Langelius *]

Over the past 25 years, I've handloaded; beginning with the then current BR handloading practices as taught me by my two older Brothers. Both gone, they would be 83 and 84 today.

It was a lot simpler then; mostly about techniques, and not gadgets. One developed a load, then produced it using basic gear and components with strict attention to consistency. At the time, factory ammo was a crapshoot, and only FGMM seemed to live up to the term "Match Ammunition". I mostly couldn't afford it and handloaded to achieve cost and accuracy gains. Digital scales were nearly nonexistent, and concentricity wasn't even a new word. Match chambers existed; but many considered them overkill. The basic F/L resizing die was about it.

Then began the proliferation of statistical profiling, manic measurements/tolerances, and gadgets enough to set the top guys back a Grand or two. I dove in head first and tried many, many of the doohickeys and mantras. They all helped, but the overhead in loading bench time was grueling. I rebelled. No group size was worth that kind of effort to me.

So I went back to basics with standard F/L dies, magazine length seating, SAAMI chambers with no concentricity testing, and the sole concession of a digital powder measure. Obviously, there had to be an accuracy sacrifice, and there was. Taking my best care shooting, it amounted to about 1/2 MOA of accuracy loss. I said to my reflection, hey Dude; you were hopping though all those hoops for just about a half MOA? That's simply ridiculous. Doing things the new (old) way, I was still shooting consecutive X's (F Open) at 1000yd.

It was an epiphany. I've never gone back. Most of this has come from better QC on dies, truly consistent and groundbreaking components, and let's not forget the Digital powder measure. Guns have come around to manifest better adherence to smaller tolerances, and barrel design is improved too. Ergonomics is now a serious subject. My key lesson was that consistency was mandatory, and that it could be achieved with fewer (none?) of the "out on a branch" modern handloading conveniences.

Decades of evolution has resulted in better understanding of the marksmanship basics. People like Frank (and there is damned near nobody as dedicated and productive) have crunched the process and derived genuine ground truth on the subjects of firearm design and shooting technique. He is the bureau of standards for the practical shooting world. And more.

I think we are in a time of change. The emphasis on hardware has delivered truths, some of which may not seem reasonable on the visceral level. I firmly believe that simpler is better, and affordability is the wormhole that our sport needs to traverse so that the playing field can be sufficiently inclusive to bring our numbers back up to where it needs to be in a world where 2A is viewed askance. The most interesting venues have become so ethereal that the new/average shooter simply looks away. It's clearly not for them, and that must change.

I used to run a state shooting program for Marine Corps Veterans. There was no prize table. We thrived.

If everyone is shooting perfect scores, the targets are too big, dummy! If nobody can shoot a perfect score, they're too small, but you're getting warm. There is no magic here.

Maybe there's a lesson in all of this, somewhere...

Greg

 

[_Raining]

We already have a way of using sample size for statistics, confidence intervals. The smaller the sample size, the larger the confidence interval for a specific confidence level. We will never get confidence intervals that do not overlap when using a level of 95% when deciding on a load recipe, there simply is no way to do it with how short of a barrel life we have. As such we need to settle for a lower confidence level. Sample size of 3 is more or less useless, 5 isn't great, 10 is much better etc.

One trick you can do is what people do for OCW without even knowing it. Simply by saying, "I am looking for consecutive powder charges or seating depth that have similar POI" you are increasing your sample size by putting 3 groups into one box. Example:

Box A = 40.0, 40.2, 40.4
Box B = 40.2, 40.4, 40.6
Box C = 40.4, 40.6, 40.8
etc

So you took 3 shot groups and turned them into a sample of 9.

The Scott Satterlee test has a sample size of 1, so even with putting consecutive "groups" into a "box" that leaves you with 3, which is still trash. My velocity graphs are basically a straight line with 5 and 10 shot groups, no flat spots (at best the slope may vary but it has never flattened out).

I think most people don't shoot enough shots but I also don't think 50 rounds per interval is necessary.

I shot a ladder test at 600 5 times. Grouping consecutive charges gives me a sample of 15.

I used Sub MOA on iOS to get the center of each Box and then used that to get the mean radius, standard deviation and confidence interval.
The numbers are basically grid values in paint but it is all relative so it doesn't matter the actual MOA value.
Box A: 1, 2, 3
SD: 17.3
Avg: 26.4
90% Confidence Interval of Avg: 19.1 to 33.7
70% Confidence Interval of Avg: 21.8 to 31

Box B: 2, 3, 4
SD: 16
Avg: 22
90% Confidence Interval of Avg: 15.2 to 28.8
70% Confidence Interval of Avg: 17.7 to 26.3
60% Confidence Interval of Avg: 18.5 to 25.5
50% Confidence Interval of Avg: 19.2 to 24.8

Box C: 3, 4, 5
SD: 11.2
Avg: 16.9
90% Confidence Interval of Avg: 12.2 to 21.6
70% Confidence Interval of Avg: 13.9 to 19.9
60% Confidence Interval of Avg: 14.5 to 19.4
50% Confidence Interval of Avg: 15 to 18.9

Box D: 4, 5, 6
SD: 22.6
Avg: 34.9
90% Confidence Interval of Avg: 25.3 to 44.5
70% Confidence Interval of Avg: 28.8 to 40.9

There is a pretty large overlap of the confidence interval for 90%. If we look at 70%, Box C has no overlap with D and A (Max C Less than Min A and Min D) but there is still an overlap with B. There is still an overlap at 60%, we need to drop to 50% to have no overlap between C and B.

Keep in mind, I did 5 shots per charge weight when most people do 1 maybe 2. So the people who only have 1 or 2 shots per charge weight are going to have large confidence intervals for %'s of 50+.

You can mock the people who advocate for larger sample sizes all you want. Statistics and probability isn't a new thing. You can ignore it all you want but the fact is there is a hidden value (confidence interval at a specific level) when someone gives you a set of #'s for their group sizes or muzzle velocities or POI and leaving it out does a disservice to the practice of load development.

If you were to evaluate 10 pitchers to be on your baseball team, would you have them throw 1 pitch each? 3? 5? Just because reloading components are expensive and barrels have a limited life all of a sudden we are OK with using low sample sizes? Like I said earlier, there is a compromise but in my opinion 1 or 3 just isn't enough. People who say "I did the Scott Satterlee test and I got amazing results" either got lucky or are just using good components in a well put together rifle.

My stats for MV and Group Size at 100 yards were (5 Shots per):
1. SD 6.1 (deleted 1 MV {first of the day}), .6 MOA
2. SD 2.6, .525 MOA
3. SD 4.6, .32 MOA
4. SD 2.2, .5 MOA
5. SD 2.8, .32 MOA
6. SD 2.8, .33 MOA
The confidence level for having no overlap between #5 and the rest is very low, I am not even going to try to calculate it since I know a sample of 5 is going to require an insanely low confidence level (%). If I did a Satterlee test, it wouldn't matter which of these groups I ended up with, I would assume it was a success because I would be happy with any of these. The problem is we want a load that is going to be resilient, to resist change; temperature, erosion of lands, imperfect charge weight (scale variance), imperfect seating depth etc. I believe Audette Ladder test with 5+ shots per interval will get me there.

 

[CharlieNC]

This is a link to a rather recent (2017) in depth evaluation by the USMC. In short, as the OP surmised the Average Radius of the shots vs center does not adequately describe the group, and the Standard Deviation of the radius must be used to obtain a robust description. Statistics heavy if you are interested.
I have toyed with this for a number of years and came to the same conclusion, but based more on intuition vs hard statistical evaluation.

Most comprehensive article I have seen on the topic!

https://apps.dtic.mil/dtic/tr/fulltext/u2/1034885.pdf

 

[LawnMM]

I’ve migrated over to using chrono data first, and then tuning the seating depth to that.

This. If your SD/ES suck you ain't hitting shit at distance so start with the Chrono. Been saying that for years.

What he’s saying is that 1/4” gun may not be as consistently a 1/4 gun as people think.

And if you shoot four groups of 5 shots each, of you combine them all, while each one might be 1/4, in totality, they are actually .7

How much of that is shooter fatigue? Low blood sugar? Hot weather?

Like Frank's always saying there's a lot of 'you' in your shooting. I also think plenty of guys are being plenty successful with 5 and 10 round load workups.

I've also, personally concluded, you can shoot 100 shot strings and have the most perfectest load ever devised, you're better off spending ten on the load workup and 90 on practice.

There's no substitution for trigger time in this game and a lot of guys are spending too much time at the bench and not enough behind the gun.

 

[chase723]

I think this will also provide some insight. While it compares structured barrels to non structured barrels it highlights barrel drift and shifting POI, which correlated with what the OP is pointing out.

Studying Barrel Drift (Structured vs Conventional Barrels)

What is the most effective way of testing barrel drift? Can barrel drift be mitigated without the use of prohibitively heavy barrels? To what degree is heat the largest contributing factor to this phenomenon. Of all the testing that Coastal has done over the last few years, this may be the most...

www.coastalprecisionconsulting.com

I think when you develop a “good tuned load” you eliminate random dispersion from a shot to shot perspective (which your chrono and target will tell you with consistently small groups and low SD/ES). However, due to material CTEs you get a physical change in the position of the barrel and so while your individual groups may not open up, the POI will shift. So, your nice tight 1/3 MOA 5 shot group will “walk” all over your point of aim potentially by more than 1 MOA. Now, your 1/3 MOA rifle after 50 consecutive rounds will likely be >1 MOA rifle in aggregate. If you can map this average POI from POA shift and adjust your offset to be in the middle of it, then you’ll be better off over a long course of fire. That said, depending on the size of the shift (which is why it’s important to cold bore map your rifle) you could be at a disadvantage for a first round impact at distance. It also lends credence to the notion that a structured barrel might offer a significant benefit in both regards. That could also, however, simply be due to the fact that they are at least 1.35” in diameter at a minimum, and structured or not that equates to an extremely stiff barrel that doesn’t heat up very fast=less barrel/poi shift.

 

[MarkyMark007]

Ledzep, do you have a number, what is average or ''expected'' move of POI for velocity ? for heavy match barrel ? at 100 YARDS !!

so how many inch ''center of the group'' goes up, if velocity is 100fps higher?

you said that this is linear, right?

Sincerely

 

[obx22]

In rimfire, isn’t this kinda like saying you don’t need the best ammo?

 

[bigpeddler]

This is a good read... pretty sure I listen to @Ledzep on a podcast.

 

[Ledzep]

Ledzep, do you have a number, what is average or ''expected'' move of POI for velocity ? for heavy match barrel ? at 100 YARDS !!

so how many inch ''center of the group'' goes up, if velocity is 100fps higher?

you said that this is linear, right?

Sincerely

It's not very much. Just looking at a couple of the extreme spreads from the ladder tests, looking at ~200-250fps swings with something like 0.1 MOA vertical shift on the averages. Anecdotally I've seen some pretty awesome 100yd groups with 100-300fps MV spread (powder thrower sticks and doesn't throw a complete charge or some other mishap).

I think in the time slice it takes a bullet that's launched at 2500-3200fps to make it 100yd you're not going to have much time for gravity to pull it down, and likewise not going to see very big differences unless you have pretty drastic changes in MV.

Slow bullets, on the other hand-- like subsonics, you can see the MV ES as vertical at 100yd readily because they've got more time for the world to pull them down.