Fitted bolt

[barretcreek]

Vendor states bolt should be fitted to AR barrel. Does this involve anything besides a pair of headspace gauges?

Found my copy of Kulek and McKee.

[lyman]

depends, if it is a custom barrel it may need to be reamed (headspace) once the collar is installed,


most are prefit, as in cut to headspace w/o any reaming needed,

[barretcreek]

Kuleck/McKee 'AR-15 Assembly Guide' details a procedure for the assembled upper. Sounds like a check for proper lockup.