When I got my used 681 and cleaned it up, I noticed the faint remains of red paint or nail polish on the back ramp of the front sight. I have since recoated that with some red nail polish, but I am wondering if what I found when I first obtained the 681 was something applied by the factory or the owner. On my 686 the back ramp of the front sight has a piece of fitted red plastic, which I assume was done at the factory.
The factory never "paints" a front sight. They install an insert of red (or different color). Paint can be easily removed with acetone and it won't hurt bluing.
681 Front Sight
Linear Mode
