Regulating fixed sight revolvers?

sjmjax

sjmjax

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What is a recommended and safe way to adjust windage on fixed sight revolvers?

I assume the process is effectively bending the barrel - frame interface and essentially move the rear sight.

I’d like to dismiss the suggestion of shooter error or technique.

I recently test six .32 caliber S&W J frame and Colt D frame revolvers at 7 & 15 yards. Separate test group with both wadcutters and with RNFP.

Four shot tight groups to POA at both distances all ammo.

One Colt & one Smith consistently shot a tight group about a hands width left of POA with all ammo and at both distances.

I suspect some may find that acceptable. I really hate guns that don’t shoot to POA with standard ammo. I’d really like to correct these firearms but don’t want to risk damaging near 100 year old revolvers.

Your suggestions appreciated!
 
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What I have done on a couple of occasions is shave the front sight. On both guns I wanted more daylight around the front sight anyway so it wasn't that big a deal. The process you describe would apparently move the FRONT sight and not the rear, but would do the job. I sort of hate to beat on 100 year old revolvers personally, but that is just me.
 
Probably the best option is to turn the barrel slightly to the left. You want the front sight to go opposite of the way you want the group to move. Front sight left, moves group to right.

You should figure out by trig how far you want to move the sight. Make the distance to move the sight side a, the distance to the target side b, and the hypotenuse side c. Then you can do a rectangular to polar calculation to get angle A. Do the same triangle using angle A and side b for the sight radius. Side a of that answer will be the amount to move the sight. No damage to the gun, simply a small adjustment.

Make a witness mark somewhere on the frame/barrel junction, and another mark on just the barrel or frame for how far to move. Then it's a simple matter of using the correct frame wrench to turn the barrel (held in the vise) to the second mark. The marks need not be permanent, just fine and clearly visible.

Sounds complicated, but would take me about 10 minutes. If you can't do the math, send me the numbers and I will calculate it for you. We need distance to target, distance to move the group to the right, and distance of sight radius.
 
Exactly as Protocall Design stated. I don't have the proper tools but I have have the ability to do it properly. I have one right now that shoots to the right and the barrel is tightened just past straight. A slight adjustment will center the POI and make the gun look perfect on close examination.
 
Protocall_Design said:
Probably the best option is to turn the barrel slightly to the left. You want the front sight to go opposite of the way you want the group to move. Front sight left, moves group to right.

You should figure out by trig how far you want to move the sight. Make the distance to move the sight side a, the distance to the target side b, and the hypotenuse side c. Then you can do a rectangular to polar calculation to get angle A. Do the same triangle using angle A and side b for the sight radius. Side a of that answer will be the amount to move the sight. No damage to the gun, simply a small adjustment.

Make a witness mark somewhere on the frame/barrel junction, and another mark on just the barrel or frame for how far to move. Then it's a simple matter of using the correct frame wrench to turn the barrel (held in the vise) to the second mark. The marks need not be permanent, just fine and clearly visible.

Sounds complicated, but would take me about 10 minutes. If you can't do the math, send me the numbers and I will calculate it for you. We need distance to target, distance to move the group to the right, and distance of sight radius.
Click to expand...

I've often wondered, "What ever happened to that kid that always asked for extra homework?"
 
Having the barrels turned sounds like the right answer. BUT, before I went thru that expense, I might try different bullet weights & velocities, as well as different grips, if you have any. Sometimes such changes can change a guns POI, even horizontally.

I tend to shoot a lot of my single action revolvers to the left, but if I rest my right thumb on the left recoil shield - problem solved.

Larry
 
If you've shot a particular gun that you know consistently groups to one side of center in its POI from its POA, just remember how much you need to adjust your aim so that POI is where you want it. With a fixed sight it is going to vary with distance anyway, so correcting the aim by altering the sights or the whole gun (??) only works at one distance.
 
I always like it when a fixed sight gun shoots POA - POI but once in a while it just doesn't work out that way. You could try different grain weights, different velocities and different brands of bullets which sometimes do make a difference. If you hand load that would be simple to try out. Other than that, on a 100 year old revolver I would not try to alter the gun to fine sight it in. Just use Kentucky windage. I am also assuming the old revolvers are for pleasure shooting, not for self defense so in this case pinpoint accuracy would not be critical.

As stated above there are other more drastic methods, however I'd not use them on vintage models. They are what they are.
 
KNOW YOUR GUN AND WEAR IT SHOOTS ,MAKE MENTAL MIND NOTES ,ITS LIKE KNOWING WHAT MY OLD MACHINES CAN OR CAN NOT DO WHEN MAKING SOMETHINGMmOST OF MY METAL WORKING MACHINES WERE NEW WHEN I WAS A BABY IN DIPERS THAT WAS OVER 80 YEARS AGO.
 
I have benched fixed sight revolvers and adjusted bullet weight and or powder charge to POA. I have never come across a case that windage can be adjusted by either. As far as grips? They have nothing to do with how the gun shoots rested and used in single action mode. They can help an individual to shoot on DA mode.
 
When the FBI issued revolvers, the elevation was changed by changing the front sight. For those who came in late, the front sights were pinned on and the cross pin was polished flush so it was nearly impossible to see. Windage adjustment was done the real factory way. I suggest NEVER watching an experienced S&W armorer make this adjustment as it will almost sicken you.

This is a pretty good discussion of the babbitt bar, the factory method for regulating windage adjustment on fixed sight revolvers:

Clarify the use of the Babbitt bar
 

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No way would I turn or bend a revolver barrel that is pinned. It's very easy to adjust point of impact left or right by filing a little off one side or the other of the rear sight notch. If point of impact is low just file the front sight down enough to bring the impact where you want it. If high just lower the front sight in the groove by trial and error to get the impact where you want it.
 
shawn mccarver said:
When the FBI issued revolvers, the elevation was changed by changing the front sight. For those who came in late, the front sights were pinned on and the cross pin was polished flush so it was nearly impossible to see. Windage adjustment was done the real factory way. I suggest NEVER watching an experienced S&W armorer make this adjustment as it will almost sicken you.

This is a pretty good discussion of the babbitt bar, the factory method for regulating windage adjustment on fixed sight revolvers:

Clarify the use of the Babbitt bar
Click to expand...

Thanks!
While I appreciate everyone’s input, that’s the information and technique I’m was looking for to correct this problem.
 
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