ATTN: Bigwheel- SA .45 LC Revolver

Okay, I put this in here as it is the closest thing we have for a forum that fits.

I shot the Uberti Regulator yesterday. About 24 rounds of .45 LC and the same using the .45 ACP cylinder. The ACP printed about the same in terms of "LEFT of Point of Aim" as the .45 LC. The ACP was not as "HIGH" from POA. Rightfully so.

I want to use .45 LC as the control cartridge, so we'll not use the ACP data at this time.

Sight Radius- 8 1/2"

Distance to target- 25 yards

Windage Point of Aim vs. Point of Impact - 2 3/8" Left

Elevation Point of Aim vs. Point of Impact - 5 3/4" High

Width of rear notch - .106"

Depth of rear notch (estimated) - .106"

Holding six o Clock on bull. Right now, I am thinking that training myself to use an alignment of the sights that places the top of the front blade lower in the vee will take care of the elevation. With ACP the windage, is, of course, off the same amount. However, the elevation is half as much too high given the lower velocity (not chrono-load data estimates)

The windage is the booger. I am trying to put an image in here to illustrate, but will have to host it (too big).

Here is the what I got .0224 or 22 thousanths it the distance to tighten the barrel
measure at the top of the sight. or right at .15 degrees. You would want to add
.044 to the top of the sight to lower it. Should be done first and then turn the
barrel because as the radius increases so will the amount of correction. In other
words same distance .0224 but the .15 degrees will lessen if done in degrees.
I would mount a wire indicator for the .0224 and move it to the indicator unless
you have a theodolite or some other way of measuring angles exactly.


Here is my math, 25 yards x 3 x 12 = 900 inches
900 divided by 8.5 = 106:1 ratio
2.375 divided by 106 = .022405 inches

In degrees 2.375x4=9.5 inches at 100 yards.

using 1 moa = 1 inch which is close enough at 100 yards we have 9.5 moa
1 degree = 60 moa. 9.5 minutes divided x 60 = about .15 degrees.

Draw it out and double check me but I am pretty sure it is correct.
you could use the exact 1.047 as moa but it only matters if using degrees.

Arright, mang. I will ruminate on those numbers during the next few days. Meanwhile, let's think out of the box.

Your figures do not represent a lot of rotation. As measured with respect to the top of the front sight, the actual amount the barrel would be turned is even less than .15 degrees.

Let us assume, for conversation's sake that the ejector and it's housing would not be adversely affected by this movement. (a pretty big consideration, by the way) One could safely assume that the "cant" of the front sight will be noticeable. Slight, but noticeable.

Now let us assume that I do not want to go to the trouble of casting a frame block and clamping the barrel in a vise. Further let us assume, for this "optional thought" that the ejector shroud will not allow the rotation. What would you say to the idea of simply bending the front sight to the left via some judicious tapping while the barrel is held in a vise ? The elevation could be compensated for by the previously mentioned adjustment of my sight picture.

I have experimented with handloads quite a bit. I have yet to change the POI at 25 yards appreciably. Using 700X and Unique, and varying the charge from below the weight suggested as a starting point all the way to 10% above max has not changed the POI more than an inch,,,,if that.

As our bro' Creator 0203 says:

Fun Times

You eye will have a hard time seeing a .15 degree cant at 8.5 inches. But the normal
way is to file one side of the sight, yours is out far enough you aren't able to
do that so bending it would be an option. They are soldered, if it breaks loose
you'll have to re-solder. But it certainly is an easier way. Just make sure you have a jig of some sort to let you know where .0224 is. the gun laid horizontal
and a caliper measurement up to the sight blade, something repeatable. I had
a hard time finding someone to do a new in the box colt because they didn't want
to mark the barrel with the barrel vise. I kept telling them, this is my shooter,
walker 57 in southern ca. porked me on it, charged me and said he rotated the
barrel, sent a target back with the gun, still shot exactly in the same place. He
was one of the big cowboy action gunsmiths. Just another low rent thief. I would
say Bob Mundon in butte mt. or cylinder and slide would be the two best bets
if you send it out. You live and learn I guess
Remember that the .15 degrees was not extrapulated from the 5/8 inch bore
center to blade tip, but from the actual moa the gun is off. I'll see if I can do the
math on the blade height and see how it matches. David

The blade is .083 wide. The adjustment you calculate is a hair over one fourth the width. I can chuck the barrel in my big vise on the welding table, set up a jig and either use my magnetic dial indicator or as you suggest, set up a fixed reference to use the calipers against.

I want to preserve the finish, but if I nick it I bet I'll get over it. You should see my Super Blackhawk. Talk about character marks. Lol

Wrap it in leather and let it rotate if it wants. Make sure you have soft jaws in
or it will tear the leather and still hit the gun. Just quick raps with a big brass
drift ought to bend it. Shouldn't mark it. That's why you
need a way to lay it down and check the distance, but yeah a dial indicator is
an easier way to go. Just have a spot to lay the gun down that is identical every
time.

Wrap it in leather and let it rotate if it wants. Make sure you have soft jaws in
or it will tear the leather and still hit the gun. Just quick raps with a big brass
drift ought to bend it. Shouldn't mark it. That's why you
need a way to lay it down and check the distance, but yeah a dial indicator is
an easier way to go. Just have a spot to lay the gun down that is identical every
time.


I got an idea on a jig. I might even get it done this week. Lol

Well the math comes out a little different on the rotation, I get two degrees.

Using 2 degrees x cosine = .99939 X .6254 (the hypotenuse of .0224 and .625)
= .625019 pretty close to the sight radius of .625

Wish I did this more often, hard to keep the order correct on this stuff when
I visit it 2 times a year or so .

You can use the 1/4 of the blade idea and go out and shoot it with that much
hold to check before bending. would be the sure thing to do. But I don't see the
math on that being wrong.

checked everything again, dividing the 900 by 2.375 is really close to 8.5 divided
by .0224 so it's right. and the 2 degrees sine = .034899 and .0224 divided by
.625 = .0358 so they are really close.