But my favorite round is the CCI Standard Velocity. Yes, boring old Standard Velocity. No hypersonic velocities, hollow points, or other modern improvements. This is the modern version of a cartridge first loaded by Stevens in 1887: A 40gr solid lead bullet in the case from the old .22 long, loaded with smokeless powder to around 1070 fps.
It's not particular fast, or particularly powerful as .22 LR rounds go, and it usually runs around $7.75/100, or about twice as much as the bulk .22LRs from Remington or Winchester or CCI's own Blazer. What it has going for it is accuracy. This is the one of the most accurate and reliable .22 round you'll find in its price range. You'll never get a misfire in a properly functioning gun, and you'll seldom get a flyer.
Now it's not the ideal round for every gun. Most shooters don't know this, but there are actually several different standards for chamber dimensions for .22 caliber guns. First, the SAAMI (Sporting Arms and Ammunition Manufacturer's Institute) Standard or Sporting .22 chamber:
Length: 0.7751"
Diameter: 0.2307"
Throat: 0.2270"
That's the spec used in most guns. It's designed to make insertion and extraction easy, particularly in semiautomatic guns. Another is the Match chamber:
Length: 0.6876:
Diameter: 0.2267"
Throat: 0.2255"
That's 40 thousandths of an inch tighter, and 875 hundredths of an inch shorter. The throat is 25 thous tighter, too. This is a spec for match guns with positive extraction- typically bolt actions. The smaller chamber spec means that the maker has a lot less leeway in machining the chamber, too, so you'll only see this spec used in expensive guns. There's also a spec for semiauto match pistols, and Winchester's own spec for the 52D rifle, which was close to the match spec, but with an even shorter chamber to insure that he bullet was seated right into the lands of the barrel rifling.
Different .22 rounds are loaded to different specs, too. Match ammunition is designed for the tighter chamber. Sporting ammunition is usually designed to work well in guns with a sporting chamber. What works well in a match gun might not work well in your Ruger 10/22, and vice versa.
The second part of accuracy in .22 ammunition is consistency. The best .22 rounds are matched very tightly from one round to the next in dimensions- particularly rim thickness - and bullet and charge weight.
The last part of accuracy is lubrication. The cheapest ammunition just uses paraffin wax. Better ammunition use mixes of various waxes, rosins and other compounds. Some careful ammunition testers have noticed that cheaper brands shoot more accurately after a few dozen higher-priced rounds have been fired, leaving some lube in the barrel, and that had led many to experiment with their own lubes. Some benchrest shooters will clean the factory lube off bullets and dip them in mixes of paraffin, beeswax, graphite, and Alox.
What does this all mean? If you'e into the high-precision .22 games, a lot. If you're not planning on spending $10-20 for a box of 50 or mixing your own lube, it's still good to know the factors that affect accuracy, as they'll help you in finding the right ammo for your gun. My pair of Ruger Mk-III pistols have SAAMI Standard chambers, and perform best with ammunition designed for those chambers. So far, CCI Standard looks to be the best combination of accuracy, reliability and price for them. My Savage-Anschutz has a tighter match chamber and only does so-so with the CCI. I may have to experiment with the better stuff to get that shooting the way it ought to.
n.b.: Here's a pretty comprehensive test of .22 ammunition using a custom rifle with a match chamber. Note that he was able to achieve sub-MOA groups at 100 yards with the CCI Standard Velocity ammo- and less than 1/2 MOA with Eley match. At 25 yards the CCI shot 0.312", which is to say that all the shots touched. And yet this tester got very different results. The moral: You really have to test to see what works in your gun.
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