6.5 Creedmoor Ammo Test Part 5: Live-Fire Group Sizes & Precision

Welcome to Part 5 of the results from my massive 6.5 Creedmoor ammo field test!

This article will cover the results from over 150 five-shot groups that I fired. There were 760 shots for record, which I carefully collected over several tedious days at the range.

When it comes to long-range, precision rifles, many of us can fixate on trying to coax tiny groups out of our rifles. After all, if you can’t hit a 1” target at 100 yards – your odds of hitting a target at 1,000 yards aren’t great. But, what is factory ammo truly capable of? We may all know die-hard reloaders that claim, “you just can’t get the precision you need from factory ammo.” Factory ammo has come improved dramatically in the past 10 years, so is that still true? What can you expect from today’s factory ammo that is marketed to be “match” worthy? This article will provide objective insight into those questions.

If you’d like to see an objective comparison of how much group size and precision matter at long range, how much it’d take to miss, or how it impacts your hit probability, I’d encourage you to check out this article: How Much Does Group Size Matter?

Quantifying Precision & Group Size

When most shooters discuss precision, we virtually always talk about group size. More specifically, we talk about the extreme spread (ES) of either 3-shot or 5-shot groups. But, just because that is the most common way to quantify precision doesn’t mean it is the most effective way.

Trying to quantify the dispersion of a group with a single number is more complex than it sounds. A group of bullet holes on a target represents a rich and complex data set, yet we want to boil all of that down to one number that conveys “precision.” Having a single number as a summary is powerful because it makes it easier to make comparisons. However, any time we simplify a bunch of data points into a single number, that implies some loss of detail or nuance, which can sometimes lead to misleading conclusions. (Learn more here)

For example, the diagram below shows two groups that have the same exact extreme spread but very different dispersion:

Here is what expert ballistician Bryan Litz has to say about extreme spread:

“When you look at the extreme spread of a 5-shot group, that measurement is determined by only 2 out of the 5 shots. In other words, only 40% of the shots are considered in the measurement. Even worse, for a 10-shot group, a center-to-center measurement is only using information from 20% of the total shots. Since the extreme spread, center-to-center measurement, is determined by only a small portion of the total shots available, it’s just sort of an indicator of precision.”

Extreme spread ignores a large portion of the shots we fired. I paid over $1 per shot for every round fired in this test, so I wanted to make sure we got the maximum benefit from every one of them! I’d imagine you might want to get the full benefit from every round you fire, so this is relevant for all of us – not just us research nerds. 😉

So what is a better method for quantifying precision? There are a few to choose from (and we could really nerd out here), but the one I’ll focus on is called mean radius. Mean radius is the average distance to the center of the group from every bullet hole. That means if you fired 10 shots, the resulting average is based on 10 measurements (i.e., the distance of each shot to the center of the group) – instead of just the measurement between the furthest two shots for ES. We effectively get more data points for free! That is a big deal because it helps us more confidently characterize and quantify the precision of a weapon system.

In December, I wrote an article that dives into the best way to quantify precision and group dispersion from a statistical perspective – but I intentionally wrote it for those who aren’t math nerds. I spent a TON of time on that article because I want all my readers to get the most benefit from the results I’m sharing in this post. I’d highly recommend you read that article if you are one of the millions of shooters who have only even used ES as your measurement of precision or this is the first time you’ve heard “mean radius.”

Here is a summary of some highlights from that article:

• Extreme Spread (ES) is not a very good measure of dispersion. “Range statistics” like ES are statistically far weaker because they virtually ignore inner data points. They are the least efficient statistics but are also the most commonly used because they are so easy to measure in the field and so familiar to shooters.
• Mean radius, also known as average to center, is the average distance from each shot to the center of the group.
• Mean radius uses information from every shot in a group, not just the two most extreme points. Because of this, mean radius can provide a higher confidence measure of precision than ES. However, mean radius is harder to measure than ES.

Mean radius allows us to accurately resolve smaller differences in precision with fewer shots. If you are comparing types of ammo or different rifles to decide which is superior in terms of precision, comparing the mean radius of the groups fired will lead to more reliable conclusions than comparing ES.

If you are not convinced that mean radius is a more reliable statistic than ES for comparisons like this, read the comprehensive article on the topic here: Statistics for Shooters: Precision & Group Size.

So What Is A “Good” Mean Radius?

One benefit of ES is that most shooters are familiar with the numbers that kind of measurement produces. If I told you I have a rifle that holds 0.3 MOA or 1.0 MOA, you’d have a good idea of the kind of precision I’m talking about. But mean radius may be new to many of us, so here is the question: What would the mean radius measure for a “good” group?

During this test, I measured the ES and the mean radius for over 150 five-shot groups fired. After analyzing that massive sample size, I found that the ES averaged 2.75 times the mean radius. It did vary some, but the measured ES for 80% of the ammo tested fell between 2.6 to 2.9 times the measured mean radius. So roughly speaking, if you measured the ES of a group to be 0.5 MOA, the mean radius might be around 0.18 MOA (0.5 ÷ 2.75 = 0.18).

Now, you can’t convert from ES to mean radius simply by multiplying or dividing by 2.75. ES and mean radius are based on different aspects of a group’s dispersion, so it’s not that simple. But, since we’re all used to talking in ES, here is a “translation table” to help us become more familiar with what the rough equivalent for mean radius might be compared to a 5-shot extreme spread (ES):

5-Shot Extreme Spread (ES)	Mean Radius
0.1	0.036
0.2	0.073
0.3	0.109
0.4	0.145
0.5	0.182
0.6	0.218
0.7	0.255
0.8	0.291
0.9	0.327
1.0	0.364

Note: I said “5-shot ES” in the table above, but remember that ES will always grow with the number of shots fired. Litz reminds us, “Mean radius will also grow with increasing number of shots, but not as much as center-to-center [i.e. ES].” So this translation table likely wouldn’t be accurate if you were comparing a 3-shot or 10-shot ES.

How I Gathered The Group Size Data

Where did the ammo come from?

I tested 40 rounds of each type of ammo and bought it all out-of-pocket from online retailers (cost well over $1,000). While I could have reached out to companies like Hornady, Berger, PRIME, Federal, and others, and they would have happily sent me discounted or even free ammo for this test – I decided to buy it all for full retail price from popular online distributors. I didn’t even tell any of the manufacturers that I was even doing this test. I paid full retail price for all the ammo to ensure none of it was cherry-picked or loaded “special” for this test. It was all just random ammo off a shelf somewhere. In fact, I ordered one box of each in December 2019 from popular online distributors, and then I waited 6 months and ordered another box of each from a completely different list of distributors. PRIME and Copper Creek only sell direct to customers, so I had to order those from the manufacturer directly. I made sure no manufacturers knew I was conducting this test. Getting ammo from different retailers and waiting 6 months between orders should ensure it was from two different/random lots, so it’s more representative of what you might experience.

What rifles did I use?

When it came to the rifle and firing process, I used two different rifles. I do personally own a couple of high-end 6.5 Creedmoor rifles, but I know most of my readers aren’t using an $8,000 custom rifle setup. Also, a particular kind of ammo might perform better out of one rifle than another because of differences in the chamber, barrel, and other mechanical nuances. Since more people use factory rifles than custom rifles, I decided to buy a stock Ruger Precision Rifle (RPR) to use in this test. Again, I bet if I had reached out to Ruger, they would have gladly loaned me a rifle for this test, but I decided to simply buy a brand new one from GunBroker.com, just like my readers would, to try to ensure it was representative and not a rifle that potentially had been cherry-picked off the line.

The custom Surgeon rifle featured a 22-inch barrel, and I decided to shoot the test without the suppressor attached (i.e. bare muzzle). I didn’t want to risk it somehow affecting the results if it came loose or somehow the heat caused mirage issues that skewed the group sizes. The Ruger Precision Rifle came with their stock 24-inch barrel, and I didn’t change a thing about the whole rifle. Both rifle barrels had a 1:8 twist rate.

Altogether, I invested a few thousand dollars into this 6.5 Creedmoor ammo research project and 100+ hours of time. I hope all of this shows how serious I am about objective testing. I am whole-heartedly in search of the real, unbiased truth to help my fellow shooters!

I realize this research could potentially impact sales for some of these ammo manufacturers, so I tried to go above and beyond to ensure the data I collected was trustworthy. I’m certainly not “out to get” any manufacturers or to promote any of them either. None of them sponsor the website or have ever given me anything for free or even discounted. There aren’t hidden relationships or agendas here. I’m a 100% independent shooter who is simply in search of the truth to help my readers.

So, as always, I tried to identify any significant factors that could skew the results and then created testing methods that attempted to eliminate those or minimize them to an acceptable level. I’ll try to summarize how I fired the groups and collected the data:

• Fired 40 rounds of each type of ammo from two different lots to have a good sample size. That was two boxes of 20 rounds each from different ammo lots purchased six months apart from different retailers.
• Fired 5-Shot Groups: To avoid “bugholes” I fired all 5-shot groups, so I could confidently differentiate the exact location of each bullet hole. I also thought 5-shot groups would be more comparable to what most shooters do.
• Target at 100 yards: I know many long-range shooters fire groups at distance, but when you are trying to quantify true mechanical precision firing at longer distances can allow environmental conditions, like the wind, to skew your groups. Firing groups at long range does let you see the cumulative effect of both group size and muzzle velocity consistency, but in this test I chose to analyze those separately (view velocity results). I will be putting it all together for a cumulative view in the next post that shows overall hit probability at various long-range distances based on all the data collected in this test. I’ll use the same kind of software analysis the military performs to calculate hit probability before launching a $1 million missile.
• Only fired groups in calm conditions: I live in west Texas where the wind always blows, but I would only fire groups for record in extremely calm conditions. This mostly meant I had some very early mornings. I hung streamers on the target, and if the wind even started to blow mildly I packed everything up and was done for the day. That was a big part of why it took so long to gather the data, but I didn’t want to risk environmentals skewing my results.
• Used professional optics and adjusted parallax appropriately: I used a Schmidt & Bender PMII 5-25×56 DT on the custom rifle and a Leica PRS 5-30x56i on the RPR. I carefully adjusted the parallax during setup each time and checked it periodically through the tests. Many shooters don’t realize how much parallax can impact group size at short range, but I do. I was careful to not allow it to skew the results.
• Fired all groups from a rock-solid position on a concrete bench using a Pheonix bipod and Edgewood rear bag. The setup, my body position, and the target location were identical for every round fired.
  

Another factor I did my best to think through and mitigate was the barrel condition. Here are some of the things I did to try to avoid potential issues related to that:

• First, I “broke in” the new barrel on the RPR by firing 150 rounds down it. In my experience, the muzzle velocity has always stabilized by that point (with mid-size cartridges like the 6.5CM), and that was true for this Ruger Precision Rifle, as well. The custom 6.5 Creedmoor had just over 2,600 rounds on it when the testing started (yes, I document every round). It was outfitted with a custom Bartlein barrel with a StraightJacket and was chambered by Surgeon Rifles. If you aren’t familiar with the StraightJacket, you should read my massive barrel test research published in Modern Advancements for Long Range Shooting, Vol 2 by Bryan Litz. (If you are reading about this test, I guarantee you will LOVE that book. I find myself referencing it more than any other book – and I’ve read virtually all of them.)
• I ran a cleaning regimen during all testing where I would start with a clean barrel and fire 4 shots that weren’t for record to foul the barrel and ensure all the cleaning solvent was out. Then I would fire no more than 30 shots for record before I cleaned the barrel and repeated the process. That would always be 10 rounds from 3 types of different ammo. The cleaning process and method were consistent throughout testing. I randomized the order that I shot the first lots of ammo in and then re-randomized the order on the second lot so that it was different both times I shot through.
• The barrels were always allowed to completely cool to ambient temperature between each 10-shot string for record.

While that is a lot of detail, my goal is to be transparent about how I gathered the data.

I used custom targets that I designed a few years ago, which helped make it very obvious if the reticle wasn’t perfectly centered on the bullseye when I broke a shot. The custom target also has a printed scale on it, making it easy to accurately calibrate a scanned image or photo of a target for software analysis. The targets print on standard letter-size paper, which makes it easy to print or scan. (You can download my custom target here: PDF | Full-Res Image. Be sure to double-check the scale on your printed targets against a ruler to ensure the program or printer you used didn’t skew the size of the image.) I used OnTarget to analyze the targets and calculate the group stats.

Called Fliers & Outliers

Of the 780 shots fired for record, I only had 3 called fliers. 3 out of 760 isn’t bad! But, remember I was on a concrete bench using a Pheonix bipod and Edgewood rear bag, so I was about as stable as you could get with a human still pulling the trigger. However, if a human is involved, you can’t expect perfection over such a large sample – so I admit I had a couple of called fliers.

What do I mean by a called flier? That means right as I broke the shot, I noticed my crosshairs weren’t perfectly centered on the bullseye. I would “call” where the crosshairs were before I looked downrange to see where the bullet landed in the group. For example, let’s say that as I broke the shot, I noticed my crosshairs slipped to the left edge of the yellow box, meaning the bullet impacted 1/4” further to the left than it would have if I had broken the shot precisely on the bullseye. The 3 times I had a called flier, I made a note of the exact aiming error, and then when I did the analysis on that group, I’d shift the related bullet hole, so the stats were correct. None of those adjustments were more than 1/4 inch, and they were on 3 different types of ammo, so it isn’t possible that could skew the results.

I didn’t exclude any “outliers.” I know some shooters throw out shots that land outside of their group as “fliers” or “outliers” – but that simply isn’t good science. Rigorous research always collects and reports on all data, which is what I will do here.

“To exclude a shot from a group just because it appears to be a ‘flyer’ is bad measurement technique and would lead one to underestimate long-range dispersion.” – A User’s Guide to Dispersion Analysis by Bruce Winker

The Results

Alright! Let’s dive into the results. All results are shown in MOA, not inches – although those are similar at 100 yards. Remember, this data below is based on over 150 five-shot groups and 760 individual data points!

Top 3

The Berger Match 6.5 Creedmoor 130 gr. Hybrid Tactical OTM ammo was the winner by a reasonably clear margin. The Berger 130 Hybrid was 9% better than the next best ammo in terms of precision. With an average mean radius of 0.208 MOA, it was 23% better than the overall average of 0.270 MOA for all 19 types of ammo tested.

#2 and #3 was a virtual tie between the Barnes 6.5 Creedmoor Precision Match 140 gr. OTM ammo and the Federal Premium Gold Medal 6.5 Creedmoor 130 gr. Berger Hybrid ammo. Both had an average mean radius of 0.228 MOA, which was 16% better than average, and 5% better than the next best performer on the list.

• 

• 

Middle Pack

12 different types of ammo landed in what I’ll call the “middle pack,” which had ranged from 0.239 to 0.261 MOA. That is over 60% of the ammo tested! There is less than a 10% difference in that narrow window, which is likely “in the noise” for this test. What I mean by “in the noise” is that the numbers are so close that I would expect the exact order of that middle pack could vary based on the boxes of ammo that happened to be tested or other factors that couldn’t be controlled perfectly in this test. If we ran through this test again 3 or 4 more times, the order of those in the middle pack would likely shift around. So I’d say all of these had a similar precision performance, at least on average over both rifles.

The next article in this series will be the conclusion and in it, we will put this group data together with all the other performance factors, like muzzle velocity, BC, and other factors to determine what the overall hit probability would be at long range, and it will help us better differentiate between the ammo that landed in this middle pack.

Bottom 4

The most apparent pattern in this data might be that most ammo tested had relatively good performance when it came to precision – except for the 4 types of ammo at the bottom of the pack. While there may not be a significant difference between the top 3 or the “middle pack,” the four types of ammo at the bottom of the list performed measurably worse than the rest.

Unfortunately, the groups for these 4 types of ammo were poor – so poor that it might be a stretch to consider them “match” grade ammo:

• Black Hills 6.5 Creedmoor 147 gr. ELD-M
• Copper Creek 6.5 Creedmoor Ammo with the Berger 144 gr. LR Hybrid
• Nosler Match 6.5 Creedmoor 140 gr. Custom Competition
• Nosler Match 6.5 Creedmoor 140 gr. RDF

Black Hills 6.5 Creedmoor ammo being on that list of poor performers may surprise many people because many see it as a top ammo company. It actually surprised me, but I’m just trying to report on the data, and the fact is it didn’t group well out of either of the rifles that I tested it in.

I tested two types of Copper Creek ammo – I had 40 rounds that were loaded with the Berger 140 gr. Hybrid bullet and the other 40 were loaded with the newer Berger 144 gr. Hybrid bullet. Only one of those ended up in the bottom 4 (the 144) – although the other was also in the bottom half. Copper Creek says they make “handmade custom precision rifle ammunition,” so I would have hoped for better performance than what these results show. While I may be tempted to chalk this up to a couple of bad boxes, remember that this was an average of 8 five-shot groups from 2 different boxes of ammo that were bought 6 months apart. So it seems likely that this is representative of what you can expect from their loading process.

Both types of Nosler 6.5 Creedmoor ammo that I tested ended up on the very bottom of the list. I’m sure Nosler won’t like to see that, but I’m confident in the data. The truth is, I was shocked by how poor the performance was. Nosler has a fairly good reputation in the shooting community, but the precision of the ammo I tested could only be given a grade of “F.”

Average ES Results

I was hesitant to publish the extreme spread (ES) data because I sincerely believe that mean radius is a more accurate way to analyze precision – but I know many of you would like to see the extreme spread, too. So I’ll share it all.

Remember ES is based on the two most extreme shots of each 5-shot group, and it completely ignores the other 3 shots. That means ES ignores 60% of the shots fired. Because 60% of the shots are ignored, if one or two of the bullets fell unusually far from the center, it has a disproportionally pronounced effect on ES.

3 of the top 4 on this list were also on top when we looked at the mean radius. One surprise is that the Hornady Match 120 gr. ELD-M edged those out and ended up with the smallest average for extreme spread, although it wasn’t by a significant margin. Honestly, I see the mean radius data as more reliable, so I won’t even guess what caused that.

The bottom 4 from the mean radius results were still in the bottom 4 here. Both types of Nosler ammo that I tested ended up with the worst extreme spreads, and they were the only two of the 19 types of ammo tested that didn’t average sub-MOA groups. Clearly, both of the test rifles were capable of sub-MOA groups with all the other ammo, but this Nosler ammo just doesn’t appear to be capable of precision.

Note: A reader asked my opinion on why the Nosler ammo didn’t perform better, and you can read my reply to that in the comments here.

Precision Differences Between Rifles

You might wonder if there was a significant difference in precision between the two rifles: the custom Surgeon rifle and the 100% stock Ruger Precision Rifle. I looked into that myself, and the data is VERY interesting!

The chart below shows what the overall mean radius was for each rifle and ammo type. The individual rifle data is based on 4 five-shot groups each, and the overall average is all 8 five-shot groups:

Over all the 150+ groups fired, the custom rifle only had a 2% better mean radius than the 100% stock Ruger Precision Rifle! What?! If you aren’t shocked by that, consider that the custom Surgeon Scalpel rifle has a price tag that is around $5,000, compared to the $1,300 I bought the Ruger Precision for off GunBroker.com. That shows the kind of impressive performance you can now get from factory rifles! Ruger, I tip my cap to you! The hard data I collected over 760 rounds shows the RPR delivers a ton of precision for the price.

Here are the overall stats for each rifle based on all the groups from the 19 different types of ammo tested:

Rifle	Avg. Mean Radius (MOA)	Avg. ES (MOA)
Custom Surgeon Rifle	0.267	0.737
100% Stock Ruger Precision Rifle	0.273	0.741

Why does the ammo perform better in some rifles than others?

Did you notice that some ammo grouped better out of the custom rifle, and some grouped better out of the RPR? The mean radius for many types of ammo varied by less than 20% between the rifles, but there were a few types of ammo where the groups varied by over 30% between the two rifles tested. In all cases where the precision varied by 30% or more between the two rifles, the custom rifle was the better performer. That means if there was a large disparity between which rifle the ammo liked, it was always the custom. However, there were 3 types of ammo where the mean radius for the RPR was 24-27% better than the custom rifle, and those were:

• Winchester Match 6.5 Creedmoor Sierra 140gr MatchKing (27% smaller mean radius in the RPR)
• Nosler Match Grade 6.5 Creedmoor 140gr Custom Competition HPBT (25% smaller mean radius in the RPR)
• Sig Sauer Elite Performance Match 6.5 Creedmoor 140gr OTM (24% smaller mean radius in the RPR)

To be clear, the custom rifle did have better precision overall – but the few types of ammo above seemed to perform better in the factory RPR by a considerable margin.

The reason one type of ammo performs better in one rifle or another could stem from a multitude of reasons. I had a conversation with an experienced precision rifle gunsmith about this research project, and he asked me specifically if I found some types of ammo preferred one rifle or the other. I shared some of these findings, and he suspected it might be related to the throat or chamber dimensions of a particular rifle or perhaps even the exact diameter of the grooves and lands of the barrels. I won’t even guess what caused it, but it was an interesting nuance I noticed in the data. I believe most serious research creates more questions than it answers, and it’d likely take another massive research project to get any definitive insight into what might have caused this.

Honestly, this is a big reason why I don’t see the goal of this research to crown one type of ammo as the definitive “best.” In fact, this type of rifle-to-rifle variance is why I tested all of this out of two different rifles. The “best” for one rifle may not be the “best” for another rifle. But, as I said right from the start, I realize that most shooters can’t spend over $1,000 to test all this ammo in their rifle. So my goal is to help them narrow down their search. Hopefully, you’ll be able to find 3 or 4 types of ammo that showed good performance in my research and try it in your rifle. It seems very likely that at least one of those will perform well in your rifle too.

Coming Up Next: Putting It All Together For Overall Performance!

While I always like to present the detailed results to my readers, I also know it is easy for us to put too much emphasis on one aspect or the other. What if one type of ammo had tiny groups, but the muzzle velocity wasn’t as consistent as another brand? What if one of the brands didn’t do great in groups or consistent MV, but the bullet has a ridiculously high ballistic coefficient (BC: essentially a measure of how aerodynamic a bullet is or how easily it cuts through the air) and has an extremely high velocity – does that makeup for it? Which gives you the best overall performance for long-range shots?

Well, there is a great analysis tool designed to help us answer those kinds of questions! I fed it all the measurements from my experiments, like group size, average muzzle velocity, the standard deviation in MV, BC of the bullet being fired, and a bunch of other ballistic data. Then I specified distances and target sizes and used that software to calculate the overall hit probability for each type of ammunition. If you want to take an objective, data-driven approach to decide which ammo provides the best performance, this is the ultimate solution! That next post will help us take all of those variables into consideration and see how each type of ammo ranks in long-range hit probability.

The next article has been published and can be read here: Summary & Long-Range Hit Probability

Find this helpful? Appreciate the content?
Sign-Up for Email Updates Subscribe for free to get an email notification when the next set of results is posted.	or …	Donate To show your appreciation and help PRB cover its costs.

6.5 Creedmoor Match Ammo Field Test Series

Here is the outline of all the articles in this series covering my 6.5 Creedmoor Match-Grade Ammo Field Test:

1. Intro & Reader Poll
2. Round-To-Round Consistency For Physical Measurements
3. Live-Fire Muzzle Velocity & Consistency Summary
4. Live-Fire Muzzle Velocity Details By Ammo Type
5. Live-Fire Group Sizes & Precision
6. Summary & Long-Range Hit Probability
7. Best Rifle Ammo for the Money!

Also, if you want to get the most out of this series, I’d HIGHLY recommend that you read what I published right before this research, which was the “Statistics for Shooters” series. I actually wrote that 3-part series so that my readers would better understand a lot of this research that I’m presenting, and get more value from it. Here are those 3 articles:

1. How To Predict The Future: Fundamentals of statistics for shooters
2. Quantifying Muzzle Velocity Consistency: Gaining insight to minimize our shot-to-shot variation in velocity
3. Quantifying Group Dispersion: Making better decisions when it comes to precision and how small our groups are