Bolt Carrier Group

[Parrandero]

In most instances the headspace of the barrel is set to the specifications of the cartridge (within a tolerance). The bolt is also made within a tolerance. There are occasions when the tolerances of the two combine to be outside the headspace dimensions, but a simple go/no go gauge is all that is needed to determine this. You don't have to have the bolt to mate the barrel extension.

So if the headspace is outside the headspace dimensions, then what?

[68WJ]

So if the headspace is outside the headspace dimensions, then what?

Unless the barrel was assembled wrong, a different bolt will usually solve the issue. The point was that, aside from custom match type builds that dial in a specific chamber dimension, anyone selling barrels will have a supply of them already assembled. Places that offer the service of you sending in your bolt are typically just checking go/no go to ensure that it is okay.

[elkbow]

i got one of these bolt/bolt carrier's in, good deal for the, equal to much more expensive units....