The Criterion Hybrid Profile has been a solid performer for my modern rifle build, and has exceeded my expectations on several fronts. Criterion’s Hybrid profile barrel is advertised as having “extreme accuracy without the added weight of a HBAR contour”.
I spent a few sweaty days in my gun-room loading up 3 loads accurate to the grain via a powder trickler and beam scale. I then chose a fourth loading, a factory Hornady Soft Point, to round out the testing.
Ten round groups are a solid (statistically speaking) means to measure barrel, ammo, and shooter performance. A ten round group gives us enough data to better evaluate accuracy and precision. The 10 round sample size is important as we all know almost any barrel could seem to be “match grade” via the cherry picking of statistically insignificant 3 round groups. Ten round groups also diminish the impact of flyers as a single flyer on the mean radius would represent only 1/10 of the group size.
For these 4 groupings, I used a bench and a standard Caldwell shooting rest.
The loads tested:
- Hornady 75 grain HPBT with 24 grains of Varget.
- Sierra Varminter 60 grain with 24 grains of AA2230
- Hornady 55 grain VMAX with 25 grains of Varget
- Hornady Factory Soft Points
The ten round groups paint a story of a highly accurate chrome lined barrel.
The max, or extreme spread, measures the distance between the two furthest points in the group. This is a data point that could be skewed by a true flyer, but never-the-less is included as it a very common data point and easily visualized reference. The problem with this method is that it factors in the two furthest points and takes no consideration of the other bullets as data points.
The mean radius measures the distribution of the group as it relates to the mathematical center of the group. This method averages all 10 data points to determine the overall average group size as it relates to the center.
I am happy with the performance of both Varget loadings and Hornady ammunition. Both the 75 and 55 grain products are highly accurate loadings that represent what shooter and barrel were able to accomplish. With a mean radius of .536 MOA for the 75 grain and .448 MOA for the 55 Vmax, these loadings represent two loadings which excel in the barrel. In particular, I believe the 75 grain loading would accomplish all reasonable short and long-range goals I could hope to achieve with this rifle.
EDIT: It seems some people on various forums are scoffing at the data. Mean Radius is a foreign method for most shooters as the more common method of measurement is the extreme spread. They are entirely different tools, and only one of them considers all 10 shots as data points. The data is the data, nothing more and nothing less. If your trouble is interpreting the data, then you need to simply read more about the topic. For those needing further info on the mean radius and why I use it to measure vs the more traditional method of measuring the extreme spread, please see Molon’s article at ARFCOM
This sample size can also be compared to what the team over at science of the gun achieved. Of note is the zero shift between each group is about a minute or so.
Continue to consider the Criterion Hybrid Profile barrel for your future practical rifle builds. Word is getting around that Criterion makes an excellent barrel. These data points will be compared vis-a-vis after this barrel assembly returns from Teludyne Tech whereby they will apply their “Straight Jacket” barrel system for a before and after accuracy evaluation. I have one extra grouping I did not showcase here… a rapid fire 20 round group of XM193 that you can see on the lead photo. That’s for comparison when I receive the SJ system back.
The Criterion product certainly excels on several fronts: It is chrome lined. It is a tapered profile so there is weight savings vs SPR and HBAR assemblies. With accurate loadings it can produce mean radius groups that are running at about 1/2 half a minute. What’s more to say? An excellent product speaks for itself.