I had my Fogger v4 for about a week when I decided I could no longer stand the loose afc ring. I dunno what version of the v4 this is, and for that I apologize. This one has an afc ring that is not threaded, and is very loose. I just want to share this simple tip with anyone having the same problem...
...automatic centerpunch. Simple. I hit it 2x, approximately 4mm between them. I did this along the smooth part of the ring, above the knurling where the ring is smooth but not to the edge. I then hit each one again in the same spots, angling the punch approximately 15* from perpendicular to the RBA. This was slightly too much, as it's a little tighter than I intended. So mess with it some.
Just wanted to share this simple tip that'll fix your Fogger v4 in approximately 30sec. GOOD LUCK!!!