Browning made a Grade 2 version of the BSS boxlock, and maybe higher too, so it's not accurate to say without qualification that BSS Grade 2s are sidelocks. I'm not familiar enough with the BSS Sidelock to know if they made multiple grades of it.
My 20 ga. Sporter has two screws on both the bottom and sides of the frame. The selective trigger is silver, barrels are marked "Assembled in Korea from Japanese components. The 12 ga. has just one screw on both bottom and sides, the selective trigger is gold, barrels are marked "Made in Japan". So color of trigger doesn't necessarily identify selective vs. non-selective. I don't know why the screw differences.
When I bought my 12 ga. Sporter new in 1985, they were available only in 26" and 28" barrels.
Art Isaacson is widely known for excellent work, and for expertise with Brownings.
Jay
Last edited by Gunflint Charlie; 02/26/13 09:58 PM.
