It can be confusing.
If you have nozzle washers, use 2.
There is a thicker washer available from CTI dealers,just for this, if you have that use 1.
Basically as in any snap ring case, you are trying to eliminate excess slop, and trying to keep the liner tight to the Nozzle & forward closure .
The CTI loads liners are a tad shorter, hence the washer/spacer solution.
I have used them both.
Jim Hendricksen
L-3 Tripoli 9693 Tap
ICBM Orangeburg SC
QCRS Princeton ILL
MDRA Price Maryland
Woosh Bong Wisconsin
"Made" member of Chicago Rocket Mafia
Rocketry...........an exact science.......but not exactly !!!