Marbles Bullseye Modification

[Nameless Hunter]

My biggest issue with this sight is the large center opening and its thin wall.
So, I made a test insert on my 3D printer. .093 ID and 3/8 OD. Big improvement for me.
Now, to make one out of metal.

 

[Spikebuck]

Your eyes must be darned good to clearly see through that small of a hole that far down the barrel! I've used a lot of peeps at the back of the breech or on the tang and while I use .093 to sight in, I have to switch that to .125 for hunting to get enough light through it for a 1/2 hour before sunrise to a 1/2 hour after sunset, which are the legal limits in MN. I agree with you, though, on that "large" middle ring, which is why I didn't like that sight when I tried it. Mine is still sitting in my Muzzleloader tackle box never used again.

 

[Nameless Hunter]

After using it for a day (shot a buck at 50 yards early this morning), I agree that a bit larger opening would work better.
The normal opening is about 0.155", so I'm thinking a 7/64" (0.109") opening would be better than my current 3/32" hole.
The BIGGEST problem for me is the thin wall of the inner ring. It just about disappears when you focus on the front sight.
The 3/8" OD of the insert really helps. I tried one with a 5/16" OD but it was not quite enough.
Maybe I should write an email to Marbles...

 

[Griz44Mag]

Hmmmm......
I have several guns equipped with Marbles Bulls Eye.
My issues: YMMV
Too close to the eyeball, inner ring turns to a GHOST ring. The farther up the barrel - the easier it is to see.
I had the same issue with the Pedersoli Ghost sight mounted on the tang, so I drilled it, threaded it, and screwed a Williams aperture into it.
Perfect. I will check the hole size on my Marbles and see if it is close enough to thread for a Williams or Lyman aperture.
The neat thing about fitting an aperture - many sizes available for hole and flange size.
You should also be able to fit a Skinner aperture on one, I have several of their peeps and they are top notch quality.

 

[Grimord]

After using it for a day (shot a buck at 50 yards early this morning), I agree that a bit larger opening would work better.
The normal opening is about 0.155", so I'm thinking a 7/64" (0.109") opening would be better than my current 3/32" hole.
The BIGGEST problem for me is the thin wall of the inner ring. It just about disappears when you focus on the front sight.
The 3/8" OD of the insert really helps. I tried one with a 5/16" OD but it was not quite enough.
Maybe I should write an email to Marbles...

Try using a rare earth magnet (3/8" OD with a 5/32 hole) stuck to the Marbles sight. You can get the magnets at most hardware stores or Harbor Freight.

 

[Nameless Hunter]

Success.
Ordered some .156" OD, .118" ID stainless tubing from McMaster Carr. Cut off an inch, chucked it in my drill and "turned" it down to .153" with some sandpaper. Trimmed to about 1/4" long, blackened it with some fire, and press fit it into the Marbles. MUCH better.

 

[Daniel Dickey]

I made one to fit in the inner ring that I like. I reamed out the hole in a 1/8 aluminum rivet with a number 42 drill bit to 0.94” and blackened it with aluminum black. A short piece of black heat shrink tubing slid over the shank of the river made a tight slip fit in the center aperture. It fit tight and I didn’t heat shrink it. I haven’t had it slip yet. The head of the rivet also makes the ring wider. You could put a washer of some kind over the shank before installing to make it even wider but I have no problem as it is. Cheap and easy.

 

[Nameless Hunter]

I made one to fit in the inner ring that I like. I reamed out the hole in a 1/8 aluminum rivet with a number 42 drill bit to 0.94” and blackened it with aluminum black. A short piece of black heat shrink tubing slid over the shank of the river made a tight slip fit in the center aperture. It fit tight and I didn’t heat shrink it. I haven’t had it slip yet. The head of the rivet also makes the ring wider. You could put a washer of some kind over the shank before installing to make it even wider but I have no problem as it is. Cheap and easy.

Even better.

 

[user 48679]

The BIGGEST problem for me is the thin wall of the inner ring.

It just about disappears when you focus on the front sight.

When a peep sight is used properly (looked "through", and not "at") and the focus is on the front sight, the peep sight aperture should not be seen.

 

[Nameless Hunter]

When a peep sight is used properly (looked "through", and not "at") and the focus is on the front sight, the peep sight aperture should not be seen.

I fully understand that the peep is supposed to "blur" out. The problem was it so thin that it just about completely disappeared, leaving me with very little reference for the front sight. Now I have a blurred peep that I "see" as a front sight reference.