I only have one that probably qualifies as an ultralight.
My Montana 7mm-08, 6lbs as shown with Talleys and a 2.5x8
Next at 7.0 lbs is a Rem LVSF .308 in a Hunter's Edge, also with Talleys and a 2.5x8
Add 2 more ounces for the Model Seven AWR in 7mm SAUM, Talleys and a 3.5x10
My heavyweight at 7.25 lbs, .338-06 in a MCM KS stock, dual dovetails and 2.5x8