That's right. You screw the back sight down until it's zeroed and tighten the knurled knob to prevent it from moving. It's a jam nut to secure the sight. I'll use some lock tight as well.

The rifle hasn't arrived yet, so I have to wait a bit before I can attach it to the sight.

Safe Shooting!
Steve Redgwell
www.303british.com

Get your facts first, then you can distort them as you please. - Mark Twain
Member - Professional Outdoor Media Association of Canada
[Linked Image from i.imgur.com]