Sighting in 1911-Style Pistol

[Doublehelix]

I have a 1911-style pistol that I am trying to sight in, and I have a couple of questions for the experts. (It is actually a 2011, but that should not matter for the purposes of this discussion.)

This is a fairly new gun for me, and I bought it used earlier this year. The front sight became loose on the first stage of a match last Saturday, I struggled mightily to get it on target. After I got home that evening, I removed it, shimmed it, and Loctited it into place in preparation for Sunday's match. Disaster. I could not hit the broad side of a barn (my new middle name is "Mike" by the way!).

When I installed it, I used my calipers to get it centered on the slide. It is pretty danged close to being in the absolute center. (Within several thousands.)

So after the disaster weekend, I took it to the range a few days ago to sight it in, and at 25 yards, it wasn't even hitting the paper!!! Ouch!

After some adjustments, I was able to get a nice tight group about 2 inches to the right of the bullseye, but I am at the limit of how far I can move my rear sight... it is bottomed out all the way to the left.

So now I am going to remove the front sight again, and this time install it off-centered a bit to the right to compensate, and the repeat the process of getting it sighted in.

Questions:

1) I have never seen this before. Normally, if I center the front sight on the slide, it is PLENTY within range of being able to sight the gun in with an adjustable rear sight. Now, I cannot sight it in with the rear sight all the way over??? Any reason why this could be happening. Should I be concerned? I was getting pretty good groups from a rest, so that is a good sign.

2) How far would be considered enough of a movement of the front sight to get this guy in the "normal range"? Normally, once the front sight is in place, I only adjust the rear sight (either with a fixed rear sight or an adjustable rear sight), so I don't have a feel for how far to move this guy. I want to start small obviously, but I only want to move it once if possible.

3) The other option is of course to move the rear sight to the left. I have not really taken the time to inspect the rear sight yet to see how it looks in relation to the slide, but the gun seemed to shoot OK before the front sight came loose, so I was just assuming that this is a front sight placement issue. Any advice here on moving the rear sight instead of the front sight. Honestly, it might actually be easier to move the rear sight than the front sight.

Thanks in advance for any advice.

Wasn't sure whether to post this here or in the gunsmithing forum. Mods: feel free to move if you feel it is appropriate.

 

[Expat]

The barrel must be visibly out of line with the slide to be that far out of kilter.

 

[Doublehelix]

The barrel must be visibly out of line with the slide to be that far out of kilter.

Ugh. I was afraid someone was going to say that...

 

[Expat]

Ugh. I was afraid someone was going to say that...

That or I guess the hole through the barrel would have to be off a bit. The line from the rear sight to the front sight has to be parallel with the bullet path under neath.

 

[Expat]

I have read that damage to the barrel crown can alter the bullet path.

 

[gmcttr]

Confirm that both the rear and front sights are centered before being too concerned. It could be that the rear sight is off center.

If there is a large correction needed, you could move both the rear and front sights to keep either one from being too noticeably far from center.

Do the math or use a sight calculator to find the amount of movement needed. "error ∕ distance x sight radius = correction needed" or Sight Correction Calculations

 

[churchmouse]

I use a bore laser to check. I can have a brand new gun near center on paper 1st mag if I take a moment and use the laser. You are to far away to just casually do this.
There has to be something else wrong here.

 

[Doublehelix]

Confirm that both the rear and front sights are centered before being too concerned. It could be that the rear sight is off center.

If there is a large correction needed, you could move both the rear and front sights to keep either one from being too noticeably far from center.


Do the math or use a sight calculator to find the amount of movement needed. "error ∕ distance x sight radius = correction needed" or Sight Correction Calculations

I did that first thing this morning with a pair of calipers, and they were both pretty much dead nuts on. The front sight was off center by just over 2 thousands, and the rear sight also within about 2 thousands, but it was harder to measure the rear sight since there isn't much room between the side of the sight and the edge of the slide.

I like the idea of moving both sights slightly, the front to the right and the rear to the left. I already drifted the rear sight slightly this morning however, so I am going to test this out before going any further and see if I can get within range.

I use a bore laser to check. I can have a brand new gun near center on paper 1st mag if I take a moment and use the laser. You are to far away to just casually do this.
There has to be something else wrong here.

I do have a continuous bore laser for both 9mm and .45 ACP, but not for .40 S&W. The only kind I have for the .40 is the kind that lights up when struck with the firing pin rather than a continuous type.

How far away are you sighting in with the laser? Do you go way out to 25 yards, or are you using a more classical pistol distance such as 10 yards?

I hear people say that 25 yards is too long to sight in pistols, but I have always used this distance. I have to do enough 25 yard poppers with this gun to justify it I think.

I did drift the rear sight a bit today ad mentioned above, but then got trapped into the "Honey-Do List" hell that comes from having such nice weather on a Saturday, and won't be able to get it out to the range to test it. I will try to get out tomorrow and see how she shoots.

 

[churchmouse]

I did that first thing this morning with a pair of calipers, and they were both pretty much dead nuts on. The front sight was off center by just over 2 thousands, and the rear sight also within about 2 thousands, but it was harder to measure the rear sight since there isn't much room between the side of the sight and the edge of the slide.

I like the idea of moving both sights slightly, the front to the right and the rear to the left. I already drifted the rear sight slightly this morning however, so I am going to test this out before going any further and see if I can get within range.




I do have a continuous bore laser for both 9mm and .45 ACP, but not for .40 S&W. The only kind I have for the .40 is the kind that lights up when struck with the firing pin rather than a continuous type.

How far away are you sighting in with the laser? Do you go way out to 25 yards, or are you using a more classical pistol distance such as 10 yards?

I hear people say that 25 yards is too long to sight in pistols, but I have always used this distance. I have to do enough 25 yard poppers with this gun to justify it I think.

I did drift the rear sight a bit today ad mentioned above, but then got trapped into the "Honey-Do List" hell that comes from having such nice weather on a Saturday, and won't be able to get it out to the range to test it. I will try to get out tomorrow and see how she shoots.

I can do 25 yards. I usually do 10 yards on a basic. That will get the gun on steel at that distance.

 

[Doublehelix]

After moving the rear sight to the left slightly, I was able to get the pistol to sight in perfectly. Not an ideal solution, but I am happy that I was able to it to work.

Thanks for all of the suggestions.