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Discussion Starter · #1 ·
I put an aftermarket front iron sight on my Mini-14, and, in order to zero, I had to adjust the rear aperture all the way to the left.
It's zeroed great now.
However, intuitively, I can't wrap my head around the "math"...
As far as left and right are concerned, (not accounting for wind variation), will my zero be the same at 25, 50, 100 and even 300 yards?
If so, how is this possible?
For example, when you set elevation zero, your line of sight and an imaginary laser line out of the barrel (bore) only meet at one point (not accounting for bullet trajectory, gravity, etc).
From what I've read online, this type of analysis or "math" regarding left/ right adjustments on the rear aperture doesn't apply ... it only applies to up and down (elevation)....
Therefore, if your rear aperture is slammed far left, apparently it's zeroed regardless of distance... theres no single point of contact as with the LOS and bore sight line analysis...
Can someone please help me and explain why?
I've been drawing pictures, using pointers, and I can't figure this out.


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Discussion Starter · #3 ·
If no force (wind, gravity from shooting sideways, etc) acts on the projectile, it will stay on the same linear course rising and dropping as it loses energy away from the earth then towards it . If you had to adjust your rear sight extreme left, chances are something is misaligned on your rig. Sight mount, barrel alignment, some other factor like rail alignment or something else is wrong.
Before I changed front sights, everything was aligned fine...
I damaged my stock front sight, so I removed it (very difficult) and installed a new Cogburn Arsenal HK style front sight... and, for some reason, I had to push the rear aperture extreme left to get it zeroed.
When looking down the rifle to the front sight, the new front sight appears square and straight... not sure what's causing the extreme deviation...
But, are you saying alignment of the front and rear sights doesn't follow the same analysis of aligning a scope, for example, with its zero (bore axis)??.. the way the line of sight, factored in with height over bore, causes your rifle to basically only be zeroed at one point?

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Discussion Starter · #5 ·
Yes it will remain zeroed regardless of distance. The reason your rear site is all the way to the left is because the front site you installed is NOT centered, it too is off to left. If the front post on a rifle is “dead-nuts-centered” the rear site will be centered. But since it doesn’t always happen that way folks may need to adjust to the right or left. When people make the right or left move they are aligning the rear site to the front site.

Now if you have a rifle with perfect site alignment and adjust the rear site to impact 1” to the right at 100yds it will be 2” at 200yds, 3” at 300yds and so on.
Ok... thanks... so, since they're now in perfect alignment with each other, they'll stay aligned...great... but, perhaps this sight alignment will always be a small amount "off" from bore alignment... lets say 1/8"... since both front and rear sights are pushed out to the left...
Therefore, the rifle will shoot straight at 100, 200, and 300 yards... but it will always be off "1/8" from true bore alignment??
It makes more sense now that you've explained the front sight must have been off to the left also. For some reason I thought the front sight was off to the right because when I had my Red Dot zeroed, which co-witnesses with my iron sights, the Red Dot was actually floating off to the right of how the iron sights lined up. Then as I adjusted my iron sights rear aperture to the left, not only were the iron sights now in alignment, but so was the Red Dot with the irons...

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Discussion Starter · #7 ·
A better question would be “as long as they all fall in the same spot, who cares?”

To answer your question I’m gonna say yes, but in really small numbers.
I haven't had a chance to compare shots at various ranges, so, I'm just doing some upfront research

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Discussion Starter · #9 ·
I agree with Mark204's posts here. But if it were me, just because something is not right with me, I would scootch the front sight back closer to center. Unless you solidly brazzed it or moving it creates risk of broken/stripped screws
I tried, but, it only loosened the sight.
The Mini-14's front sight is secured by a roll pin that slips through the front sight along a small cutout on top of the barrel.
When I tried to move it, the roll pin and tight fit were compromised, so I had to hammer a metal dowel through the roll pin to puff it back out and make it tight.
The only thing I can think of is my aftermarket front sight must've been off centered some how.. as I mentioned above, everything lined up cherry before I switched sights

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Discussion Starter · #12 ·
Ding, ding, ding…..we have a winner. :p
... I also mentioned above that the stock oem front sight broke, and, therefore had to be replaced.

So, I replaced it.

Then I was surprised at how off center the rear aperture looked.

Then I turned to Rugerforum.net for insight...

Sometimes these forums provide great knowledge to newer rifleman/ gun builders... other times, it acts as a platform for jokes and wisecracking.... just gotta take the good with the not so good

Btw- ruger said they would replace my front sight under warranty... but, they are typically required to return the rifle in stock condition.
I've made some mods to my Mini-14 and didn't want to hassle with sending it in and all that.

Here is the same rifle shown with different stocks and red dots.
I've added an accuracy systems harmonic Barrel stabilizer, a .050 reduced gas bushing, a Yankee Hill Machine Phantom flash hider, a Samson Manufacturing Hannibal rail, a recoil spring buffer shim in front of the action, Mcarbo sear spring replacement, accutech rear sights, and Vortex viper on the wood stock set up & Vortex Strikefire ll on the tactical set up.
For the tactical stock, I swapped out the butt stock with a FAB defense GL-CORE stock.
The rifle runs great.


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Discussion Starter · #15 ·
Just thinking out loud, OP, but is it possible that the barrel was slightly bent when the OEM front sight was damaged, AND/OR could the barrel have been bent when the OEM front sight was removed?

The barrel being slightly bent is one possible explanation for the undamaged OEM front sight working OK, and the New front sight not working OK.

It is also possible that the New front sight was mis-made, or mis-installed. (No offense!)

Speaking only for myself, I would not be content with the rear sight being set far from its' center in order to hit a target at range.
I don't think there's any barrel damage because the red dot never had to be readjusted.
I'm pretty sure something must be misaligned with the new front sight.
The barrel has a groove on the top that accepts a roll pin which passes through the new front sight post, so, there's no way to adjust/ twist the front sight left or right- the roll pin locks it in.


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Discussion Starter · #17 ·
Ok everyone- I'm a dumbass... somehow my rear sight block got knocked out of position. I straightened it back in place, and everything is back in alignment. I'm not sure how my rear sight block could have moved so much, I guess my wife was messin with my guns again.

After considering everyone's feedback, I was going to run a string line from the center of the rear post to the front post and look for misalignment, that's when I noticed the rear sight post block was out of whack. Sorry to waste everyone's time


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Discussion Starter · #20 ·
Well... sorry to report that after adjusting my rear sight post block, I still have to move the aperture significantly to the left. Not quite as far, but still pretty far. According to the detailed post above me, it appears that I can't reuse the drilled out portion of my Barrel to install the new front sight post. It appears I have to drill a new Groove after aligning the new front sight post.


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Discussion Starter · #21 ·
I can’t speak to how Ruger aligns it’s sights at the factory, but the design whether it’s the old style sight or the newer winged sight uses a pin that fits in a hole drilled through both the sight and about a half pin diameter of the barrel.



Normally, when you are fitting a new front sight to a Mini 14 or rifle with a similar sight design, you ensure it is zeroed (in windage at least) and then clamp the action or barrel in a vice to prevent any movement of the rifle and adjust the vice and or a target dot so that the sights are aligned on a target dot several feet or yards away. You then remove the old front sight, slip fit the new front sight and rotate it until you have proper alignment of the rear sight, front sight and target. Then you drill the new hole through the sight and barrel. Using that approach you don’t end up any worse off than you were with the old sight.

Choate front sights come with a divot in the side of the sight that allows you to center the pilot drill, and with a drill press or milling table, you get a nice properly trued hole through the sight and barrel, and then you upsize the hole to the final dimensions.

Lacking a jig, getting things not to move from the vice to the drill press or milling table can be accomplished with one of the green loctite compounds designed for cylindrical fit operations and you have a few minutes to align things before it sets up. 641 has a lower maximum temp of 300 degrees F which makes it easier to remove the sight if you screw up the alignment or wand to replace it. 620 withstands a temp of 450 degrees for at least 30 minutes, and up to 600 degrees F for shorter periods. Choose wisely based on your needs.

——

Several years go I bought a Mini 14 ranch rifle as surplus from the NC department of corrections. It had a monstrosity of a muzzle device that served as bayonet lug, flash suppressor and front sight. The device was pinned, but unfortunately the front sight was on the opposite end of a rotating piece that held the bayonet lug. The set screw provided was not enough to hold it in place. NC DOC didn’t care as they scoped their rifles.

But it meant that when I replaced the front sight I had no baseline for alignment of the new front sight.



However, since I was using a Choate front sigh, which like the old style Ruger sight has a lot of surface area in contact with the barrel and was a snug fit to start with, I was able to zero it without drilling the sight. I wrapped a piece of tape around the rear of the sight and another piece of tape behind it on the barrel. I made an index mark on both pieces, rotated the front sight as needed to zero the rifle in windage and then made a second set of index marks.

Given that unfortunate barrel already had two holes in it from the two prior front sights, I wasn’t real excited about drilling another hole in it. I degreased that section of the barrel as well as the inside of the sight and used Loctite 620 to secure the sight to the barrel, using the alignment marks to ensure proper alignment. I then shot a group to confirm it was dead on with the rear sight mechanically centered before the compound set up.

I let it cure and then out a couple 30 round magazines through it rapid fire to bring the barrel temp up as hot as I’d ever anticipate it getting and didn‘t even get half way to the 450 F mark at the front sight location per my infrared thermometer. As such, I didn’t bother drilling and pinning it. It’s never moved or loosened.



——

Looking at your replacement sight it appears to be 3D printed and designed to use the existing hole in the barrel with holes already present in the sight. That makes installation easy, but proper zero with a mechanically centered rear sight, would require a) the new front sight to be identical to the old front sight, and b) the rifle close enough in overall mechanical alignment that Ruger didn’t have to drill the original hole very far off the vertical.

That doesn’t appear to be the case with your rifle and sight.

You could move the sight slightly fore or aft so that it still covers the original hole and drill a new one, after using the above process to get proper alignment. The challenge will be hitting the hole on the opposite side of the sight when you drill from the front side through the barrel. That takes very precise alignment with a drill press or mill.

A crutch there is to drill the hole half way through from both sides. A roll pin should be flexible enough to negotiate any minor alignment error, and the error is now on the inside where it doesn’t show.

You could also just use Loctite 620 and see if you have enough surface area to secure it.
Thanks for the detailed response. I installed one of those Choate sights on my other mini-14, and I ended up using epoxy to set the new Choate front sight to zero, and once it was set, then I drilled the new hole through the top of my barrel.

I guess I can't use the existing drilled out Groove that secured my factory front sight for the new front sight. It sounds like I will have to drill a New Groove for the new front sight, or just deal with keeping it slammed all the way to the left...

When I drilled out the groove for the choate front sight, I used a portable drill press and it worked out great.


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Discussion Starter · #22 ·
"proper zero with a mechanically centered rear sight, would require a) the new front sight to be identical to the old front sight, and b) the rifle close enough in overall mechanical alignment that Ruger didn’t have to drill the original hole very far off the vertical."

- from Model52

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Discussion Starter · #25 ·
You say you damaged the front sight, are you sure that is all the damage that was done?
Yes.
The red dot I had on before changing the front sights still held zero.
There's nothing wrong with the barrel/ gun.
It has to do with not reusing the same groove in the barrel for a new sight.

The red dot held zero, and accuracy is consistent with the red dot before and after.

Apparently, the amount of movement in the rear aperture isn't the same as with the corresponding movement to the front sight.
The front sight just doesn't look that off... but, you can clearly see the amount the rear aperture is moved off center to get the irons zeroed

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