Current 6mm Grendel barrel makers: BHW, McGowen and who else?

[Sticks]

...Plan on working up 70 gr FB Tipped Varmageddons for use on p-dogs out to 600 yards for that upper (yes, I found a dogtown where I can park my truck, pitch my tent and rain lead down from a hillside from 500-700 yards away - give the buggers a fighting chance against my wind calls!). ....

I may have to come pay you a social call.