Hope this is the right place for this

[Kev308]

Is there a formula to figure out how much I need to remove from my front sight to get a 50 yard zero? Thanks
Kevin

 

[64Springer]

Take a few swipes with a file and shoot it.

Take a few more swipes with a file and shoot it.

Take a few more swipes with a file and shoot it.

Stop filing when you reach your zero.


Math is great, but not when it comes to all the different variables presented with muzzleloading firearms.

The math for a ball being pushed by a 50 grain charge will be different than the math for a ball being pushed by an 80 grain charge.

This is why it's important to find your most accurate load first.

Then file the front sight for that load.

 

[Phil Coffins]

Is there a formula to figure out how much I need to remove from my front sight to get a 50 yard zero? Thanks
Kevin

D2 = R2 (D1 X R1)
D1 impact error
D2 sight change needed
R2 sight radius
R1 inches to target

 

[reddogge]

Good advice above:
1. Develop your most accurate load first.
2. File and shoot, file and shoot, file and shoot
3. Drift front sight is necessary for R and L.

 

[#blackpowderbill]

Shoot at 25 yards. A dot
Get your group
Is it high low left right?
Adj left right
Shoot to see it it moved for you.
Now is the group low or high?
Then file a little bit ,front or rear; at a time.

 

[Pete G]

In the words of Jimmy Buffet “Math Sucks”

 

[Kev308]

Thanks for the help guys. All the homework has already been done, as far as determining the load goes. I had shortened the barrel and replaced the sight. I crazy glued the sight on it, because I wanted to get the sight right before I soldered it on. As it turns out I can file it as is, going to be interesting trying to get that sight off…..

 

[Dwight Rutherford]

Thanks for the help guys. All the homework has already been done, as far as determining the load goes. I had shortened the barrel and replaced the sight. I crazy glued the sight on it, because I wanted to get the sight right before I soldered it on. As it turns out I can file it as is, going to be interesting trying to get that sight off…..

Acetone should work to get the super glued sight off.

 

[Philip Lebow]

Sight radius (in inches)
Divided by distance to target (in inches). Times the impact error distance (In inches)
Equals the correction dimension (usually in decimal fractions of an inch)

 

[Col. Batguano]

Sight radius (in inches)
Divided by distance to target (in inches). Times the impact error distance (In inches)
Equals the correction dimension (usually in decimal fractions of an inch)

Correct. I usually file the sight to be pretty close to the formula, and then shoot, just in case something was amiss in my calculations. Because it's easier to remove material than add it.

This is of course AFTER I've done my initial test firings. Before I shoot the gun I start out with my (rifle's) front sight a little bit higher than the rear sight (as measured from the barrel centerline), and then adjust from there. While it's a general rule of thumb that that's going to automatically have your groups print low on the target, that's not always the case, particularly in the cases of hard recoiling short guns. Case in point; I have a 10" Thompson Center Contender in 30-30 Win that I have to have the scope centered about 10" above the bore-sighted centerline in order to even be on paper at 25 yards!

 

[Scota@4570]

You can mathematically figure it out by completing two triangles. I used to do that.

I make a leather with a slot to protect he barrel from the file.

Find an accurate load. Shot a group. Then look at the front sight and compare the width the amount you are low.

Say the sight is 0.060" wide and you are 6" low at 50 yards.

Say the width of the front sight looks about 5" wide on the 50 yard target.

Filing about the width off the top will bring you up about 5".

I would file off half of what I figured, shot another group, then file more as needed.

 

[Flint62Smoothie]

FORMULA
The 'Formula' is relationship, where 'A is to B' is the same as 'C is to D'. This is expressed as A/B = C/D, where:

• A = The amount the sight (front or rear) needs to move (or be filed, where possible) in inches
• B = The distance between the sights in inches, or the sight radius
• C = How far away your impact is from your aim, in inches
• D = Distance in inches, at whatever yardage you shot

Example:
Let's say your 2" low @ 50-yards. 'A' is what you want to know. Let's assume you have a sight radius of 28", then 'B' = 28". 'C' = 2" and 50-yards in inches = 50 x 3- feet per yard x 12 inches per feet, so 'D' = 1800 inches.

Using the formula: You have A/28 = 2/1800. Then you cross-multiply (top to bottom of each!) to get, 1800A = 56 (or 2 x 28).

Solve for 'A': Divide both sides by 1800 results in A = 56/1800, or 0.311" or about 1/32th of an inch that the front sight needs to be filed DOWN to raise the point of impact.

NOTE - If you are printing high, you can't UNfile the front sight to lower the impact, but you could get a taller front sight or file down the top of the rear sight (if you have material to do so) and deepen the notch as needed. But be careful there, you need a thin file so as not to inadvertently widen the sight notch.

 

[Col. Batguano]

Slight correction to your formula example. It's not 0.311", but 0.0311"