How much to file the front sight

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The barrel is A weight Southern Classic 50 cal. So I bent it, took almost an inch of belly to get .040. Here is the rear sight, the bending set up and the target from 10 minutes ago. Filed the sight down to .150 and the highest shot that says file is the best I could do and I may have pulled that as I wasn't getting much change with 10 strokes of heavy filing. I filed between almost every shot and the shots only went up 2.5 inches except for that one. I filed almost .100 off before the first shot. It appeared as I got .040 of bend in the barrel and it moved it up to where I'm happy to go ahead and finish the gun. I'm also very pleased with the group, all are about 1.5 inches wide and the last 3 I didn't file and that's about a 1 inch group. I did raise the powder to 65 gr, .022 patch and .490 ball for all shots. The shots to the right were from the other day when I was trying to get it on paper, I was aiming at the top of the target board for the few you see. POI should of been POA on the target and the target is 40 yds. Thanks to all, Phil
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That is a unique rear sight I see the dilemma.
 
i just received 4 of those sights from TOTW. They have 2 sizes but that is in the base. what is the height to the center of the aperture from your barrel flat? i will measure mine, maybe they vary in height. they are hands down my favorite rear sight.
Sight is about .275 inches from the barrel flat. I have both sizes and both are about the same height + or- depending on dovetail depth. I use mine with 2.00 readers and a 5/8 inch black circle with a 3/32 peep stuck on the glasses in the correct position for sighting.
 
BARREL BENDING
FWIW I’ve successfully bent rifle barrels when desired not to move the sights way out of kilter … full octagonal & part oct/part round.

IMPACT 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.
 
I lowered the center of the barrel about .040 which is the equivalent of raising one end .080. With a 42 inch barrel and 28 between the sights, that's like taking a little less than .060 off the front sight. I think that falls in line with the calculation above. raised the point of POI 3 or 4 inches a 40 yds. You can get it close then fine tune with a file.
 
deepen the notch as needed. But be careful there, you need a thin file so as not to inadvertently widen the sight notch.
I find it easier to work with a file that has safe edges.
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The barrel is A weight Southern Classic 50 cal. So I bent it, took almost an inch of belly to get .040. Here is the rear sight, the bending set up and the target from 10 minutes ago. Filed the sight down to .150 and the highest shot that says file is the best I could do and I may have pulled that as I wasn't getting much change with 10 strokes of heavy filing. I filed between almost every shot and the shots only went up 2.5 inches except for that one. I filed almost .100 off before the first shot. It appeared as I got .040 of bend in the barrel and it moved it up to where I'm happy to go ahead and finish the gun. I'm also very pleased with the group, all are about 1.5 inches wide and the last 3 I didn't file and that's about a 1 inch group. I did raise the powder to 65 gr, .022 patch and .490 ball for all shots. The shots to the right were from the other day when I was trying to get it on paper, I was aiming at the top of the target board for the few you see. POI should of been POA on the target and the target is 40 yds. Thanks to all, Phil
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Thanks for sharing, I first saw something about barrel bending on a YouTube not too long ago. This seems like a much safer way than that guy did, he just cranked it in a vise and started reefing on it. Did you use a straight edge and feeler gauges after bending to see how much deflection stuck? Does the bend stay where it's at (.040) or does it have some memory that will creep back to, say .038 after the first few firings?
 
Thanks for sharing, I first saw something about barrel bending on a YouTube not too long ago. This seems like a much safer way than that guy did, he just cranked it in a vise and started reefing on it. Did you use a straight edge and feeler gauges after bending to see how much deflection stuck? Does the bend stay where it's at (.040) or does it have some memory that will creep back to, say .038 after the first few firings?
That's a steel bench and the 3 steel blocks are 1.25 inches, one on each end and one 20" from the muzzle. Don't know why, I just felt that was the point to bend it. The center block had about .080 on top (it's a swamped barrel), before I started turning the clamp. I made several attempt at bending before I got the results I wanted .040 which took almost 1 inch of bend. I was looking for .030 but settled for .040, which worked fine. I checked the barrel again after I shot and cleaned it and it stayed the same. The tapered piece of steel sticking out about 12 inches is a tapered feeler gauge which I used to check my progress.
 
Buchele recommends starting out with a rear sight that is about 1/16" higher than the front. But I see you have a fancy peep sight, so....
Also, on a swamped barrel, carefully consider sight placement to avoid major alignment issues.
I see people are quoting the formula from Leonard Walline's fine article on "Understanding sight Adjustment" from "Muzzle Blasts" Dec. 1998. Might want to look that one up.
 
Buchele recommends starting out with a rear sight that is about 1/16" higher than the front. But I see you have a fancy peep sight, so....
Also, on a swamped barrel, carefully consider sight placement to avoid major alignment issues.
I see people are quoting the formula from Leonard Walline's fine article on "Understanding sight Adjustment" from "Muzzle Blasts" Dec. 1998. Might want to look that one up.
As you can see on the target, 2 inches to the right which should be easy and I'm there. The sights where online with the bore at the start, rear sight was push down the barrel for better focus. (Old eyes) Never seen the formula, but it's just simple math and angles. I think the barrel was off, that's what my figuring told me. That's the reason for bending the barrel. From the way I lined the sights with the bore it should of been close, not 10 inches low at 40 yds, which would of caused me to have to file most of the front sight off or replace the rear sight with a inortanery high rear sight.
 
Yes, from Track of the wolf, works well for me. Sometimes I use it in conjunction with peep stuck on my glasses. Today was without the peep on my glasses, I was in a hurry. Old eyes I need all the help I can get.
me being the metal worker that I'am I would either built a complete new one or soldered a piece of banding material to it in the shape I wanted
 
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