BTW in the link above regarding Green Mountain barrels there was a match chamber and a stinger chamber available. What's the difference?
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A match chamber is a little tighter than the factory chamber so that when a round is chambered the bullet actually is pushed into the rifling thereby eliminating any jump between the bullet and the chamber this aids accuracy. I have fired many sub-sonic, standard, and high-velocity 22 rounds through my Green Mountain match chamber barrel without any problems.
The CCI Stinger has a muzzle velocity of 1640 fps that is 300-350 fps higher than high velocity .22 and they generate much higher chamber pressures. Also if I remember right Stinger .22 rounds have a slightly longer case. If fired in a tighter match chamber can be dangerous. So the barrels with a Stinger chamber are cut to handle these rounds. The factory chamber is OK but a match chamber and Stingers is a no-no.
The match chamber seems to be good all around. If you want an accurate rifle that shoot best with standard and match ammo and can use standard case high-velocity for hunting the match chamber is the way to go.
If you want to use Stingers you have to have the Stinger chamber. If your primary use will be hunting using Stinger ammo the Stinger chamber is the way to go. IMO getting a Stinger chamber and then shooting standard .22 in it defeats the purpose and will hurt your accuracy.