I would agree that peeps can be effective mounted further up the barrel. That said, all of our eyes are different and a forward mounted peep may not work too well for some if mounted far away from the eye. I've personally tried two different types mounted up the barrel, one being the adjustable one shown in this thread and a fixed one sold by ToTW that looks very traditional. For some reason, my eyes don't seem to do well with a peep being far up the barrel...open sights with the notch cut wide enough so I can see daylight on each side actually work better for me up there. So I mount peeps back around the tang and I use a .125 diameter hole size in the aperture which works from a 1/2 hour before sunrise to a 1/2 hour after sunset....our legal shooting hours in MN.
I have mounted Johnson peeps on numerous rifles and really like them. Here's one I mounted on a Flint Hawken I built where I added a thin dovetail to it. Because of having a hooked breach, it HAD to be mounted far enough forward so I could pivot/lift the barrel up to remove it. This one worked out VERY well mounted in this position.
Here's the view through the peep with the camera about where the eye would be when shooting.
Here are two 4-shot 50 yards groups taken while I was at the stage of final sight adjustments. For me...I'll take them.
Here's the brass version mounted on a Jaeger I built. This is the position I personally prefer. A tip on the brass version: If mounted with a bit of overhang over the curve of the tang, you can drill and thread a hole right behind the aperture mounting on the base and insert a small set screw that if tightened down a bit will actually bend the base up a little for some fine vertical sight adjustment. Just a warning that the base is not a "spring" so it won't naturally go back down if the screw is then backed off. Unfortunately, I don't have a picture of that possible modification.
Again, camera is at the position the eye would be at.
Target results at 75 yards. Funny...that hole marked "not mine" was a modern rifle guy who was at the range that day and came over to look at my flintlock. I asked him if he wanted to shoot it. That was his first shot EVER with a muzzleloader of any kind at 75 yards (bench rested, of course). He was pretty excited.
Hopefully these pictures give those who might want to give the Johnson peep a try a view of what it looks like when sighting through it at different distances from the eye. Results can be the same either way.
