Help me understand accuracy and barrels

[Forrest r]

At the same time a better rifle will get better accuracy out of low-grade ammo than a lower grade rifle. Even when it's not the preferred ammo, a CZ 455 will do better than a stock 10/22 with the same ammo.

The real problem with 22lr/accuracy/low cost firearms is the fp/ignition. CZ's are excellent firearms and with some bolt & trigger work will flat out shoot. Back in 1996 I bought a NIB CZ 452LUX, back then they were imported by MRI in minneapolis MN and had triangle shaped boxes.
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Now their imported to KC and have square boxes. Always liked that pencil bbl'd CZ lux and in 2008 while I was building that 10-22 I worked on the bolt on the cz lux. Did a bunch of polishing and moly treating the parts along with a heavy duty striker spring and re-shaping the firing pin tip. I used the russian Vostok ammo as a test bed. A lot of people bought the vostok ammo over on rimfire centeral and had issues getting it to go bang when they hit the loud button. I saw that and said good & bought a case of it to test firearms with. What the fp hit looked like on the vostok ammo after the bolt was re-worked.
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That cz lux had no problem doing 1/4" 5-shot groups @ 25yds. The problem was it could only do 1/4" 5-shot groups @ 25yds. After the bolt re-work the groups were cut down by +/- 40%. Typical 5-shot groups after the re-work. Note the 31* jan-31-08 ohio winter temp the day of testing.
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Same rifle doing 50yd 5-shot groups. The result is listed in mm's because I was doing a 50yd 13mm game over on rimfire centeral.
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I owned/shot a lot of rimfires over the decades & tend to lean toward the sporter rifles. I do own/use bull bbl'd target rifles, but I don't shoot them that much anymore and have been thinning the herd. Sold my last winchester 52d this year along with a remington 40x. I can easily say shooting 22lr's @ 50yds is childs play compared to 100yds.

[KCSO]

Don't forget the rim thickness gauge for the ultimate in accuracy. Although with enough experiment and work a factory barrel can shot groups better than most folks think.

[cuzinbruce]

I have built two 10/22 rifles, mostly aftermarket parts. One has a Shilen barrel the other has a Feddersen barrel. One thing to be aware of with tight chambers is that you may not be able to EXTRACT an unfired cartridge. The Feddersen barrel extracts fine. The Shilen not at all. You have to shoot it out, use a cleaning rod or the point of a knife under the rim. Shooting it out is quickest. The 10/22 guys seem to accept this but I see it as a major liability. A real safety issue. Consider: at the range and they call for a cease fire. You are hunting and want to put the gun back in the car. Someone else is using the gun and is not aware of the issue. Both are accurate barrels. The bolt jams the bullet into the rifling on the Shilen barrel and the 10/22 extractors can't pull it out, they slip off. That is with factory and aftermarket extractors. A bolt gun might have more leverage but not a 10/22. Something to be aware of.
One easy upgrade for a 10/22 is the new BX trigger group. $50-60 for a whole trigger group with a much better pull.
That is my two cents.

[arcticap]

Barrel temperature can also affect point of impact with both target rifles and pistols.
Having shot .22 Bullseye matches in freezing cold ranges where no warm-up shots are allowed,
I would wrap my pistol in a hot gel pack before leaving the house to help simulate a warm barrel.
Even when my kid would sight-in to shoot in Junior 3-position matches, the bullet impact can climb as the barrel warms,
And that was indoors at only 50 feet.