cci velocitors very tight to close bolt

[Tommy Tree]

Hi, have a cz425 American.I'm setting up a scope and am trying different types of ammo to find the most accurate.I tried cci velocitors but find them very tight to close the bolt.They seem to fire ok though not that accurate.Any ideas why they are so tight going in?Cci subsonics are very accurate.5 shot groups less than 5/8" at 80yds.

[painter]

They're likely long for the chamber.

CZ doesn't recommend CCI Stingers because the bullet is longer. Even CCI SV has a longer driving band. You can fel the extra resistance, but the bolt closes.

[Tommy Tree]

Hi painter.I measured the length of the bullet to the top of the driving ring.The subsonic are .77" and the velocitors are .80",so that's definetly why it takes a little more pressure to load.Thanks.

[tlnzz1]

As painter has mentioned:

From the FAQ on CZ's web site:

Q: ?Can I shoot CCI Stingers or long-for chambering Sub-Sonic ammo in my CZ??

A: Our .22 LR rifles are built to tight tolerances for increased accuracy, and our chamber is what other manufacturers might refer to as a ?Match? chamber. The tight tolerances mean overly long cartridges may not fit, so Stingers and some large sub-sonic loads will be too long to allow the bolt to close. Also, we warn customers against using sub-sonic loads because of our tighter bores.