I have around 55 submissions in my Casey DNA project and co-admin Brooks that has 200 submissions. 90 % are R1b submissions spread across four clusters (just created a four this week based on a new L21+ and L226- results. Two are L226+ and many distantly related. The other "grouping" is my challenge - probably SRY2627+ which has some extremely common DNA values. Plus I also have two non-Irish haplgroups E and J for two Casey lines. A lot of similarities with my Casey Surname project - bet your surname is clan based as well since there are not many clusters plus L21+.
I have one extremely strong branch in my South Carolina Casey branch - this cluster has a very recent MRCA of 1700. Half of the proven lines have 460=12 and half of the proven lines have 460=13 - very rare marker values. We have another strong genetic branch - but it is due to two submissions of the same oldest proven ancestor. If others test positive for this mutation, they would be closely connected to this line. We also have two somewhat weak branches - based on the infamous fast moving CDY markers.