I'm having selective threading issues with my RSST. It screws down onto my CCTS and my Vamo just fine, but it will only go about two turns on the Provari and then it just stops. I tried using a 510-510 adapter, got it about half-way on, then had to get out the pliers to get it back off. I got the RSST from a vendor offering a "great deal," which in hindsight, I think is vendor code for "irregular batch." I wasn't planning to use it on the Provari, but still ... Before I get another one (cuz I love it otherwise), I just wanted to try and confirm that this is a QC issue and see if it's widespread or peculiar to the batch from this vendor. Anyone else having similar problems?