Got The Rifle To Group, However Exhausted Sight Adjustment

[Mule Brain]

Never shot this rifle before, and today was the first run with it.  Shots are at 25 yds

I was aiming at the target on the left, and you can see where they were landing. Started off with FF .490 ball with .20 denim patch.
Moving up to FFF it really started grouping as notated. However.........  The second target was three shots after windage adjustment nearly to the max.

I really can adjust any more windage on the barrel. I have the front sight all the way to the right of upper flat, and rear is really off to the left.   

Advise on how to remedy??

   



Best I could get it after sight adjustment

 

[D. Taylor Sapergia]

MB:  pls. take a close up picture of each of your sights...may have suggestions depending on what you have....

[Mule Brain]

I will get pics posted up of the sights tomorrow, after it gets cleaned

[Daryl]

Now Mule Brain, your barrel is either bent, or the hole is not in the middle just back from the muzzle. It could be 3" or 10" from the muzzle, but it's "out" somewhere - either bent or crooked inside.
Pressure from a crooked stock would not do that to that extent unless it was barely a slip of a barrel, very skinny with a horridly crooked, way overweight (strong) bent stock.

I had a barrel just like that.  It was a .50, with the holes in the middle at each end. Trouble is, the hole took a bend to the left, almost to the side,
 then swung back into the middle again. This cause the rifle to shoot WAY to the right, just as yours was.

I re-barreled the rifle, or rather that Taylor did that work and the new barrel shot centre with both sights in the middle, as it should.

[alacran]

If the barrel has excessive run out and the run out is oriented horizontally, you will get the results you have posted. If you don't mind filling in dovetails, re orienting the barrel so the run out is vertical will solve the problem. Much easier to deal with .

[Mule Brain]

I have also submitted this info to the barrel manufacture, and look forward to their response.

   

[recurve]

I was lent a Thompson center renegade in.54 one yr for the Pa flintlock season,  It grouped but way to the right , the sight at max adjustment, I used Kentucky windage was on paper till 35yrds . later after I returned the rifle I thanked & told the owner about the sights he laughed and said " that was my uncles rifle it HAS NEVER killed a deer"  LOL. 
I found out later at Dixons that some of the barrels had a "run out problem," drill wondered to the side and not found before leaving the factory.  the rifle still hasn't killed a deer.

[Top Jaw]

You could take the barrel out pull the breech plug and inspect to see if there’s run out oriented horizontally. If not the barrel is probably slightly bent. There are some threads on here about bending barrels that are interesting. I wouldn’t be afraid to give it a try - especially since you’re out of options on the sites, or if the manufacturer doesn’t have a workable option for you. 

It’s tedious because you have to bend then reinstall then shoot then bend then reinstalled and shoot etc. Some people mentioned bending in the field in the sharp fork of a tree.👍.  If you were careful you could probably lay the barrel back in stock without putting the pins in and just a tang screw and shoot it off sandbags to get everything where you wanted it, including sites more centered.  Maybe a temporary low profile small C clamp or strap clamp at one of the thimbles.  Some guys reported significant improvements as I recall.

[Mule Brain]

Here is pics of the barrel

[rich pierce]

A couple things that could be camera angle artifacts:
The notch in the rear sight looks off center.
The end of the front sight blade closest to the shooter looks closer to center than the front of the sight which is closest to the muzzle.

[snapper]

I was anticipating sights that were farther out based on your comments.  IMO you still have quite a bit of adjustment left.   The picture shows your front blade is not parallel to the barrel.

Fleener

[Mule Brain]

Don't go based on the current sight configuration. I knocked the rear sight back in closer to center for now, as I didn't want to lose it.

 

[smylee grouch]

I think Rich might have it right. If so you can take the sights out of the gun and file a small amount off the offending side so it wont hang out past the dove tail. Also configure your V notch so it has a "knife edge" on the muzzle side and flat on the rear side. This can help give you a sharper sight picture.

[D. Taylor Sapergia]

I'm pretty sure Rich is describing making the top of the notch on your rear sight as thin as you dare.  This greatly improves the sight picture - clarifies - so that your sights and the target all appear to be sharper.  Here's an example, the sight I made for my Kuntz rifle.

[Daryl]

The rear sight notch appears to be to the right of centre and the front sight's rear(toward the shooter) appears bent to the left.
Both of these defects, bring the sights business ends closer to the middle, even though the bases are right and left of centre.
Since the bore appears centered at the muzzle, the problem is likely a bent barrel OR the bore is off centre just back from the muzzle,
as mine was.
Off-centre bores at the muzzle or breech resulted from bores that were drilled in octagonal blanks, aka  Douglas of the 70's and 80's.
Today, most often the bores are  in the middle, both breech and muzzle as the holes are drilled & rifles in blanks, THEN those are
chucked (held) on centres and then the flats are ground or cut after all interior work is done. The result is centred bores, breech
 and muzzle.
If the problem isn't merely the rear notch not centered and the front sight crooked and if a piece was cut from the muzzle of your
barrel, then the hole/bore would likely be not in the centre. Drills sometimes wander. Most often this is caught by the manufacturer
but not always.

[kudu]

Step 1.
I think most of us seem to believe your front sight is NOT parallel with the barrel.
It looks that way? fix that.

step 2
shoot another group.

Step 3,
I have sighted a gun with the rear sight way over to one  side.

THEN made some calculations and made a New rear sight blank with the Notch purposely off center to compensate. I don't like the look but most don't notice.

After some thinking I would Probably flex the barrel I described it in the post just a minute ago "How to compensate".

[Mule Brain]

The manufacture wants to see the barrel to check it out, they think the barrel may have gotten bent in shipping.

So I will ship it to them, so they can check it out

I will post what they find

Regards   

[Brokennock]

I agree with Rich that the notch in the rear sight looks off center, to the right which would make the gun shoot to the right. Maybe widen the notch slightly, only removing material to the left, leaving the muzzle side of the notch wider than the side near your eye. This and fixing or replacing the bent iron twisted front sight should fix things up. And are definitely worth trying before bending your barrel.

[Mule Brain]

Disregard the notch on the rear sight, that was done after the shooting was done. It will be corrected later.

Sending barrel to builder after the Christmas rush

 

[heinz]

What are the dimensions and caliber on that barrel? The photos look like a really serious swamp and a big bore.

[canadianml1]

If I understand your posted message/target properly, there was an error of about six inches at 25 yards. If the POI is 6 inches to one side of the POA at 25 yards the sight adjustment required to zero is nearly 1/4 inches at the front or rear or 1/8 inches at both (for a sight radius of 36 inches). Since this amount of adjustment is not practical either you change the style of shooting or load ( to help correct error) or bend the barrel.(prorate for different POI error and/or sight radius). ie six inches error at such a close range says there is something wrong with the barrel or something drastically wrong with the way the rifle is being held JMHO. Best wishes for a successful result.

[Marcruger]

I have to agree with what was said above.  You have a bad barrel.  Either bent or with runout.  I am very glad to hear that the barrel maker is still around, and that he will make it right. 

My personal opinion is that if a gun is new and shoots like that, you need a replacement barrel.  I know they bent wrought iron barrels in the past, and folks do it today, but I would not want a "correctively bent" barrel in my new gun.  Too many unknown internal stresses in the metal that may cause accuracy questions.  If it is an old gun bought used, you have nothing to lose in trying to bend it. 

Runout - I am surprised how many folks today don't know about runout, or check for it before putting a barrel in a gun.  Runout is where the bore in the barrel is not in the center of the outside of the barrel.  The hole is at an angle so-to-speak.  It is less common today, so I think folks ignore it.  Check both ends of the barrel, on all flats, to make sure the wall thicknesses are the same all around.  In the old days, good barrel makers checked this, and marked the runout narrowest thickness side with the makers name, intended to go face down when the gun was built.  Runout up and down is no big deal, the sight height takes care of that.  When any other flat goes face down, you get a horizontal issue on target.  Bad. 

I had a flinter built in 1983 I bought second hand.  The runout was side to side, and with the sights hung off to one side, it still shot 6 inches left at 50 yards.  The builder simply installed the barrel with no thought to runout.  I also had a light, swamped barrel that got bent in transit, that ended up being replaced. 

My stomach sunk when I saw your target.  That is only 25 yards, so it will be even worse at 50 yards or further.  Take the barrel out, and find a flat surface, and rotate the barrel.  You'll be able to see if the barrel is bent.  I could measure under the swamp on the bent barrel I had and see the bend. 

I wish you the best of luck with this.  Hopefully it will also point out that barrels still need to be checked. 

God Bless,   Marc

[Sparkitoff]

I know we stick to traditional stuff here, but in this instance a little modern assistance wouldn't hurt. You can get a laser bore-sighter. Most have a .50 caliber arbor and smaller, some even a .62 and .73 (for 20 and 12 gauge). It will quickly tell you if the barrel is bent right or left. Another simple way that could work it to get a small flashlight with near bore diameter and use some tape to center it. Concentrate the beam and you'll see if it is projecting to one side. In either case if you figure it is bent you know what you are dealing with.

[Daryl]

A long straight edge laid against the barrel will show if the barrel is bent - as Marc noted. Holding the edge on the flats and on the corners
one end to the other should show any differences from one side to the other, if it is bent.

[John SMOthermon]

I had similar issues once...I re-centered both sights and started the sight in process again, it worked.

You’re sighting across the barrel as the sights are set now..... it appears.

My rear sight notch was filed a little off center as well. Which I corrected during the process.

The front sight appears too be bent/ angled  as well, but could be just the camera angle as Rich said.