I bought a couple of 75mm AT reloads about a year ago to use in CTI hardware and so far I have not been able to use them.
My first problem was that 75mm AT reloads don't come with a forward seal disk. AT wants you to use their reusuable aluminum seal disk, but they have been unavailable everywhere for a long time. I finally got one today from csrocketry.
So right now I'm trying to assemble an AT 75mm 3 grain L1150 in CTI hardware. Now my problem is that apparently I have no grain spacer O-rings. I checked in the other 75mm AT reload that I bought, a K1000, and it also has no grain spacer O-rings. Do AT reloads use grain spacer O-rings? It shows them in the instructions. If so, where are the grain spacer O-rings supposed to be packaged in an AT reload? With the grains?