What % pg/VG u using? With higher VG content, I find mine clogg after 6ml. A quick rinse/dry burn clears this up.
I have 2 t3's, I rebuilt the 1st one after a week to perform better on my 650 ego, rebuilt at 1.7ohms. The second is the 2.5 head that came with... using it on a twist at around 4.2-4.5v... same deal with both, need cleaned/dry burnt after 6ml. A higher pg ratio, and I may get 8+ml, but still using it and on week 4