In a recent article in Guns & Ammo on the benefits of sorting .22LR ammunition Dave Emary came to a few conclusions.  Dave is Hornady's Senior Ballistician.  To make a long story short, he concluded that measuring rim thickness is the least worthwhile sorting method.  Based on his experimenting the most significant factor is bullet runout (concentricity), and bullet head height being the next most important.

It should not be a surprise that runout is a contributing factor since sorting for runout is a common technique with high power precision shooters, but it’s not typically associated with rimfire ammo .  He noted that he’d never heard of measuring .22 ammo head height which is the measurement from the base of the cartridge case to the top of the bullets driving band.  It’s an interesting article.  Since I have all the necessary gauges including a RCBS concentricity gauge I recently completed measuring 15 cartridges of several brands.

Attached is a spread sheet with the results.  As expected, the more expensive ammo was better than the cheap stuff.  But there were a couple of surprises.  I expected the cheap Win Wildcat to be worse than the data suggested & was a little surprised to see how well the RWS R50 turned out.  It was no surprised that the Win. bulk plinking ammo was the worst of all the stuff I have.

Although Dave’s article I mentioned there’s little or no value in sorting by rim thickness, it’s easy to do.  And based on other articles, weighing .22 ammo is not considered beneficial, but I was also curious.  Determining head height was quick using using Hornady’s comparator with .22 insert.

Measuring run-out (concentricity) was by far the most tedious measurement. Concentricity gauges are made for larger cartridges.  I was able to use my RCBS Case Master Gauging Tool but it took some practice to develop the necessary technique due to the small size of the cartridge.  Setting up the spread sheet, entering all the data required a good bit of time, but was necessary to utilize the statistical calculations.  I was not about to do it using a hand calculator.

Overall this exercise was very time consuming.  I did it out of curiosity & have no plans to continue sorting .22 ammo.  And I do not plan to test fire the sorted ammo.  BTW, I use CCI Std. Target for silhouette chickens & pigs, Eley Match for the turkeys & rams.

Wayne

Eagle eye Bill Lawrence spotted a major error so I corrected the data & posted it later in this thread.

A dog's age ago I did a sorting study aimed at determining whether swaging cheap ammo (think Paco Kelly, but I used my own tool).  Tedious doesn't begin to describe it.

Using the Eley Match cartridges as an example, with all 15 cartridges having a head height between 0.720 and 0.730, how can their average height be 0.681 rather than 0.72x?  (The same discrepancy applies across the board.)

Bill Lawrence

Eagle eye Bill, thanks for catching that.  It's because I screwed up and used the wrong correction factor for the comparator gauge & the average calculation included one to many values.  Rather than the correct 1.0026" I used 1.026".  Thanks for catching my error.  Through the magic of spread sheets it was easy to correct all the data as follows.

Wayne

When I shot .22 matches I found the most worthwhile sorting for my time put in was simply weighing cartridges. Anything more didn't make it worthwhile for me, and just got too time consuming for the return. But weighing quickly and easily culled out rounds that I'm sure would have been flyers.

Cbashooter wrote on Feb 15^th, 2023 at 9:58am:


Some years back, I was playing with a US Model 1898 Gallery Practice Rifle, the Springfield Armory answer to the Stevens-Pope replacement barrel.  IIRC, it had a groove diameter of .2265 and an 18" twist.  Paco Kelly made me a tool that would cover the large diameters.  Tedious is a good description for both the tool and the rifle.

I then got a Waltz die that would size bullets to .226.  It worked in a standard C-type loading press, with a shell holder that fit .22 rimfire rims.  Easy to use. I could resize 10 or 15 cartridges in the time that it took to resize one with the PK tool.  It also came with a note that said "for cheap ammo only.  Do not use with good ammo."

I tried the Waltz tool on 2 boxes of the German-made Wolf Match Extra.  That was my choice for "most points per $".  Resizing destroyed the accuracy.  But resizing worked with stuff like Remington Thunderduds.

Years back the whole concentricity deal ran wild throughout the RFBR world until it was shown with  a match chamber it yielded no benefit.
Playing with mid priced ammo still yields mid performance ammo. 
Depending on your requirements, there is simply no substitute for match ammo. Fully recognizing not everybody is willing to drop $ on match ammo but all the other stuff…….you’re kidding yourself.
That said, lots need to be matched with guns.
Even then…..it shoots or it does not, and if you get good, selected  stuff……pull it and shoot it.