I have a Model 336 made in 1948. I have a Williams Receiver on the rear and a Skinner .5” front sight that was installed recently. Yesterday I was able to get out and shoot it for the first time with the new Skinner. After getting close at 25 yards I backed the target up to about 100. The group was centered elevation wise and about 1.75”, but 6” to the right.

I am able to adjust the Williams rear sight fine but I don’t know how much the graduations and markings are set to move POI at 100 yds. Anyone know? Google has been no help.

I don't remember, but the Williams or Brownells page has the info.

Did you replace the factory buckhorns?
First impression of the Williams?
What were your reasons for choosing it?
What others did you consider?

Looking at adding aperture sight to 336, leaning towards the Skinner, at the moment, can't decide.

I left the factory buckhorn to keep all parts intact and it was not in the way. (Have the factory front in the safe). Got the receiver sight to improve accuracy and I’ll take under 2 MOA for a 71 year old rifle with Federal Blue Box ammo. I love it. Plenty of room to find the front post while not being so large as to preclude accurate shooting. This was a Christmas gift from my father so I didn’t really look into others. Would have liked to keep the factory front but it was 19” high at 100 yards and the peep was bottomed out.

I checked the Williams website but couldn’t find that info. May check Brownells.

Thanks

It'll only cost you shooting a few more rounds to find out.

How much to move the sight, or how much the POI moves with each click depends on your sight radius. You can skip to the bottom for the easy answer but the formula shown here works for any open or peep sighted firearm - handgun or rifle.

Assuming this is the old standard Williams Foolproof, the windage screw is 40 tpi so each full turn moves the sight .025". At 20 clicks per full revolution each click moves the sight .00125".

To calculate sight adjustment use the formula (X / sight radius in inches) = (POI correction needed / distance to target in inches). X is the amount you will need to move your sight. Plugging some numbers into the equation:
POI correction needed = 6"
distance to target = 3600" (100 yards)

You will need to measure the sight radius, within 1/4" is fine. Just for example let's say it's 24". Simplifying the equation with those numbers you get:
(6 * 24) / 3600 = X, solving for X you get .04". So you'd need to move the rear sight .04" to the left. .04 / .00125" per click = 32 clicks left windage.


Went through the preliminary math just for the heck of it, but all you need to do is use (6 * sight radius) / 3600 = distance to move sight. Plug in the actual sight radius in inches on your 336 and you have your sight correction. Sight correction divided by .00125 = number of clicks.

Move it some and see. Don’t over think things.

I got an email from a Rep at Williams. Based on my 27” sight radius each graduation should be a little over 3” at 100 yards. I moved it 2 tick marks so we will see. Thanks guys. Jim his calculations were basically what you posted. I can copy and paste the email if anyone wants that info?

Here is the text of the email from Williams:

What I can tell you is that for a 27" sight radius, adjustment moves at the rate of 127.32 MOA/inch. So if you're moving in 1/40" increments, each graduation (of .025") will yield a 3.183 MOA movement.

3.183 MOA/IN; 1/40" graduation=
- POI Change: 3.183" @ 100

The problem with this method of calculation is that each line is approximately .015" wide itself; which means that changing your adjustment the mere width of the line will move you 1.91" @ 100; which is why we say that those graduations are really for reference only.

Interesting comment about the graduations. Is your sight a Foolproof (nowadays they call them an FP) or a 5D? IIRC the 5D doesn't have click adjustments but the aperture just slides back and forth and is held in place with two lock screws.

If it's the Foolproof then never mind this next part. But if someone wants to get slick with the 5D and has a set of calipers you can still measure where the aperture is now in relation to the end of the crosspiece, then set the needed change on your calipers and lock them down, then use that to set the aperture very precisely. This also works well on the sliding set and forget types like a Skinner or XS that don't have any reference marks or click adjustments of any kind.

I grew up with peep sights and have converted a half dozen or more centerfire and rimfire rifles from scopes back to peep sights over the last few years so this is kind of a pet topic of mine.

Based on what I saw on their site I thought I had the 5D but the guy I have been emailing back and forth with said the 5D did not have adjustment lines. I’ll have to rummage through the box in the safe to see if I still have the packaging. But I’ll take the info from the email and see how it works.

Shoot it at 50 yards with the tighest grouping ammo it likes

Do it on a 1 inch grid target.
Use 4 clicks for an adjustment baseline

Record the results of how much 4 clicks moves impact.



Double the amount of movement it has at 50 for 100 based on 4 clicks for reference , but confirm it also.



Maybe it might even work with 8 clicks as your base line

Range results with your rig will give ya the answers.

You can get all the advice on the planet their is to be had.

Range work is what is gonna tell ya what ya need ta know.