Moving my front sight

[Bugman]

My rifle seems to consistently shoot a little to the left: At 50 yards about 4 inches west of center, at 30 yards about 2 inches west of center. So, I need to shift the front sight a small amount to the left relative to the barrel. Before I embark on this adjustment, I would like some advice from the forum on what has worked well for them. I had a friend recommend using white-out on the barrel and sight and then make a witness mark before tapping the sight to mark how much I moved it. I don't know how successful the removal of the white-out would be; I don't want to mar the finish on the barrel. So, please gentlemen, some suggestions.
Also the rifle shoots about 2 inches south of center, but I thought adding a little more powder might remedy that - yes/no???

 

[azmntman]

uhhh...what kinda gun ya got?

 

[hawkeye2]

White out or acrylic craft paint will come right off without leaving a mark. Paint a line on the sight and barrel and you can see how much it moved by looking at the edges of the mark, no need to bother with a witness mark.

As for elevation more powder may or may not change things. Decide on your ball diameter, patch thickness & powder charge first and then file.

 

[Zonie]

To correct for a 4" error at 50 yards, the correction factor for the sight is .0022.

Multiply this number times the distance between your sights to give you the amount you will need to move the sight.

For instance, if the distance between the sights is 20" we have 20 X .0022 = .044"

If the sights are 30 inches apart we have 30 X .0022 = .067"

Drifting the front sight is best done with a piece of soft metal between the hammer and the sight.

Brass or copper works well so if the base of the sight is exposed, holding a penny against it and tapping on the penny might do the job without leaving any marks.

 

[Bugman]

Zonie and Hawkeye, thanks for the suggestions. The math sounds good for a start.

 

[Gene L]

A piece of masking tape with a witness mark will serve as well as whiteout.

 

[Eric Krewson]

Have you run out of adjustment room one your rear sight?

 

[Larry (Omaha)]

As for elevation more powder may or may not change things. Decide on your ball diameter, patch thickness & powder charge first and then file.

hawkeye2 is right on. :thumbsup:

If you have dial calipers take a reading before you move the sight. You will always know where you started from.
Flitllocklar :wink:

 

[robinsroost]

I was always taught to move the rear sight in the direction you want your shot to move. Unless you have run out of room to move the rear sight, leave the front sight alone. If you must move the front sight, move it in the opposite direction you want the shot to move. Keep yer powder dry...”¦”¦..robin :hmm:

 

[stubshaft]

I just use a plain pencil to mark the original position. Use a brass rod or punch to move the sight.

 

[Col. Batguano]

I've found that front sights that are much off of center have a way of looking a little odd. You might get away with 1/2 a blade width, but generally moving the rear sight is less objectionable. If you have a flat topped rear sight you can even file off the overhang once it's adjusted and make the 2 sides even. That would be even less noticeable.

Generally your east-west POI won't change with your loads, but some times they do, particularly in the standing position. It's just that most guys don't shoot well enough in standing to be able to get a good read on group size and center to know if another 1/2" worth of adjustment is warranted.

 

[Danny Ross]

I also use a pencil as a witness mark on the barrel. I place the the mark on the edge of the front blade that I am moving the site away from. If I am moving it left I mark the barrel on the right side of the blade. When I shoot if I didn't move it far enough I wipe off the old mark remark the barrel and move again. Before you move anything though make sure you aren't canting the barrel when you are shooting, that can throw it off.

When moving sites: The rear site you move in the direction you want the round to hit. The front site you chase the round. Hold your index fingers of both hands in front of you with your arms extended so they are in a straight line. If you move the front finger/site to the left, you have to move the rear finger to the left to keep them in line. If you move your rear finger/site to the right you have to move your front finger to the right to keep them in line. Hope that makes sense. DANNY

 

[Pete44ru]

I apply a strip of common (yellow) masking tape across the barrel, almost touching the sight, then make a pencil mark on the tape, at one of the sharp corners (or center) of the sight.

When the sight's moved, the distance is easily seen by comparing the mark on the tape with the new position of the sight's reference point.

 

[Bugman]

Zonie, I'm curious. How did you arrive at the correction factor of .0022?

With a distance between sights of 31.25"; 31.25"x.0022=.06875" looks excessive.

Where am I wrong?

 

[Zonie]

50 yards times 3 = 150 feet times 12 = 1800 inches distance to the target.

@ 50 yards you said it was shooting 4 inches off the point of aim.

4 inches error divided by 1800 inches to the target = .0022 error per inch of travel downrange.

.0022 times 31.25" of distance = .06875

Of course, we don't need to worry about the number to the exact thousandth of an inch so moving the sight 1/16 inch (.0625)or just a little more will get you very close to being right on.

 

[nhmoose]

I just take the gun to the range and drift the sight and try 3 shots. Any less on shots you a chasing the shot.

Group does not move enough drift it again and repeat.

When it goes the other way take it back a tiny bit.

Need precise measurements [get a set of measurable it seems modern ones] not really, unless you want to do all the suggested measurements for some reason?

 

[Rifleman1776]

I just take the gun to the range and drift the sight and try 3 shots. Any less on shots you a chasing the shot.

Group does not move enough drift it again and repeat.

When it goes the other way take it back a tiny bit.

Need precise measurements [get a set of measurable it seems modern ones] not really, unless you want to do all the suggested measurements for some reason?

Only good response yet. Right on. :applause:
Ye can't zero a rifle on the keyboard with numbers. No way, no how. :shake:

 

[Twisted_1in66]

Once you get it centered, take a metal punch and punch a small dot in it near the edge. That will make a small bulge in the edge that will keep it from moving on its own or from incidental bumps while handling.

Twisted_1in66 :thumbsup:
Dan

 

[dodger]

I just take the gun to the range and drift the sight and try 3 shots. Any less on shots you a chasing the shot.

Group does not move enough drift it again and repeat.

When it goes the other way take it back a tiny bit.

Need precise measurements [get a set of measurable it seems modern ones] not really, unless you want to do all the suggested measurements for some reason?

Only good response yet. Right on. :applause:
Ye can't zero a rifle on the keyboard with numbers. No way, no how. :shake:

I guess vernier sights are redundant .
Also mathematics are superfluous .
The Piraha tribe have the answers we seek , they use only the numbers "one","two" and "many" and "few". :slap:

But personally , I use the ancient English method , to wit, the Gnat's Cod and Firkin unit of measurement, which is infallible and precise .

When adjusting front sights one taps it over the width of a gnat's cod ,which might be too firkin much . In which case, one tap's it back half a gnat's cod which will be just firkin right .
Works every time !
:rotf:

 

[Caterpillar Hunter]

I'm a believer in doing the math first. It helps me from drifting the sight too far. Like Zonie said, set up a proportion: distance between front and rear sight (31.25") divided by distance to target (1,800.") is equal to X (distance your sight will be moved in inches) divided by 4". That will give you 0.069". I sometimes use a caliper to make an ink mark (0.069" wide line)onto masking tape for reference.