308 Stainless Barrel, less than30 rounds through it

Action has been timed and trued

Need some opinions on an extraction problem.

The bolt is not hard to open.
The bolt is hard to pull back, requires a hard tap with your palm to remove the spent case
The case (Winchester Factory Ammo) has minor rough raised surface at the case body and shoulder interface
Hand loads with LC brass and 42.0 Grains of Varget are not as hard to extract and have minor surface roughness in the same area as the Winchesters but no raised metal (harder cases?)
The headspace is correct
Any ideas what is causing this, or have a solution?