Hey Cayugad, I went outside with the empty gun about twenty minutes after sunset and took a sight on my neighbor's dog about forty yards away (she would have had a heart attack if she'd been home). I could see OK with the 1/4" insert in place - but with the inserts out I could see real well through that 1/2" hole. No matter how dark or shadowey, if you can see it with your naked eye you can see it through that big hole. With a good bright front sight (ivory bead?) you could probably shoot in moonlight.

Try taking a strip if cardboard 3/4" wide and 2" long, put a 1/2" hole in one end, bend it into an "L" shape, and tape it to one of your barrels. You'll be amazed.