I think my issue is the 35 Whelen barrel diameter was too great for the UM unit to property tighten down. It simply slid further up the barrel to the point where a couple of my slings weren’t long enough.
There is one on mine, but you’ll have to ask Whelenut how he got it on there.
As I recall, on a 35R or W, the trick is to start tightening the screw on the band with the band closer to the muzzle until it catches, then slide it down and do the final tightening. It's been a while since I've done this on a 35. It's a PITA, but they do work on a 35 bbl.
