Peep sight inserts.

[SierraHunter]

I recently inherited a Marlin 45/70 from my father. It is a first year production Marlin 1895 rounds bolt model. It has a prototype side mount receiver sight on it with click adjustments for range with a cam inside that is adjusted to a specific load. Pretty nifty. I believe it was the only sight produced, as the fellow who made it died after sending this one to dad for testing.

Anyway. Somewhere along the way dad took the aperture out of it, I’m guessing to be able to see better as he got older.

Now the problem it, I don’t have a aperture that will fit it. I have some Williams and Skinner apertures, and they are too small for the sight.

So, before I spend money on ordering parts that may or may not work, does anyone know if Lyman or Redding apertures have a larger size threaded shake then the Williams ones?

[Drm50]

Lyman, Redding, Redfield and Williams are all the same. First thing you need to do is figure out what size and thread you have.

[Flailguy]

If you can find the size and thread pitch i needs to be anyone with a lathe could make one.

[samari46]

Most American sights all use a standard 7/32x40 threads per inch.
Redfield made some of their olympic,international and palma sights with what I'm guessing larger aperture threads for the european market and metric threads. I have one but has an adaptor that goes from the larger threads to the standard threads.

[SierraHunter]

I wouldn’t doubt that it’s metric. I believe the sight was built in Canada.

[M-Tecs]

On one of customs the only way to tell is to measure. Not an easy task for the average person on fine pitch internal threads.

One option would be to send it to these folks and see what they have that fits.

http://www.aperturesnmore.com/main.sc

How did the foot turn out?

[OS OK]

From this web site...
http://www.meritcorporation.com/products.html

Scroll down to... Merit #3 Discs

Available in two styles - Master and Target.
Aperture varies from .022 to .125 inches diameter.
Internal click spring maintains aperture setting.
Positive internal stop to protect from excessive torque.
Thread sizes available for most sights: 7/32-40, #10-32, #10-40.
Threaded shanks available in three lengths.
See size chart for proper length.
A metric adapter available for use on European 9.5mm-1mm threaded sights.

Don't know if this will help or not? I don't know much about these gizmos other than they are a lot of fun to use!

[SierraHunter]

On one of customs the only way to tell is to measure. Not an easy task for the average person on fine pitch internal threads.

One option would be to send it to these folks and see what they have that fits.

http://www.aperturesnmore.com/main.sc

How did the foot turn out?

The foot healed up fine.

[GregLaROCHE]

Take it to a place that sells various size bolts and with trial and error, find the one that fits the threads. Then you will know what they are. You may even be able to use the bolt that fits as stock to be machined on a small lathe.

[Irascible]

Merit has seemed to have gone the way of the DODO bird. Ebay sellers seem not to know anything about threads. If you find a bolt with the correct thread, you can alwyas use a lathe and drill a center hole of the size you want.

[SierraHunter]

That may be the way I end up going. I have a set of thread pitch gauges around here somewhere.

[Shawlerbrook]

Yes, unfortunately the Schenectady based Merit has been gone for a while now.

[samari46]

Give Champio's choice a call. They offer many rear sights with other than standard threads and possibly still have the adaptors. Or send them the sight and see if they can see what thread it is
and possibly fit an adaptor and a new peep sight. A lot of the Anschutz shooters use the gehman eye pieces those are I'm not mistaken are metric. Redfield used to sell their Olympic, International and Palma sights with metric adaptors installed. I have one with the adaptor but it goes from whatever large thread back to the standard 7/32x40tpi. Frank

[john.k]

If its a one off prototype ,its possibly got a standard screw thread to mount the eyepiece.....simple enough to see if it takes a correct sized coarse or fine machine screw.

[Drm50]

I was going to buy the tap & die for standard American receiver sights and apertures. They are pretty pricey. I’ve got an old South Bend lathe, it would be a job to make something that small. Some of the cheap ladder sights have 1/4 x 28 threads.

[SierraHunter]

It is very possibly a metric thread since it was made in Canada.

[swheeler]

Take it to a place that sells various size bolts and with trial and error, find the one that fits the threads. Then you will know what they are. You may even be able to use the bolt that fits as stock to be machined on a small lathe.

This right here

[1hole]

Gun screw threads run much finer than standard SAE threads. Few off-the-street connector dealers will even know what thread you need.

[rockshooter]

You might try the local Ace Hardware. They are rumored to carry gun screws- to find out what size you need.
Loren

[Idaho Mule]

You tried Williams/Redfield apertures. So, do you need bigger? or smaller to fit your sight?