I've had two barrel assemblies fabricated for TCR-87 guns in 20-ga with fully rifled barrels. One barrel blank was an E.R. Shaw and the other was a Verney-Carron, made in France and sold through Hastings. The Verney-Carron barrel is much smoother than the E.R. Shaw barrel. When clean it is about like looking down a glass tube. The edges of the rifling are sort of radius-ed and shallow. The E.R. Shaw barrel has a couple rough spots on the corners of the rifling which seem to catch plastic from the plastic sabots of slugs or cloth from cleaning patches. However, the E.R. Shaw barrel seems to be at least as accurate as the Verney-Carron. They was an article in one of the gun magazines a couple years ago or so where it was said that E.R. Shaw barrel quality is much better than in the past.