Colt Police Positive fixed sights adjustment

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dahermit

New member
I have recently purchased an old Colt Police Positive in .38 Special. The reason I bought it was that I have never owned, studied or worked on a Colt double-action before. I have always wanted on to compare lock-works of Smith & Wesson to Colt double-actions, and this was my chance.
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Wow! What a heavy double-action pull! I suspect that this gun was carried a lot (by a right-hander, inasmuch as the right grip panel is quite worn), but shot very little (as the heavy trigger-pull would discourage much shooting).
I did a search on Colt double-action lock-work and refreshed my memory as to fix the heavy trigger pull by putting a bend in the mainspring. It worked beautifully. Double-action trigger is now light enough to actually use. It improved the single action pull also.
However, the gun shoots way left of the aiming point (See photo of target). It shots about seven inches to the left of the aiming point at 17 yards (my home range standard handgun distance). I am using 2.7 Bullseye with a 148 grain wadcutter.
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My primary interest is that I do not care for the remedies that I am aware of that are commonly suggested for shifting the point of aim inasmuch as I want to keep the old gun stock condition. Therefore, I am not interested in having an adjustable rear sight installed. Bending the front sight reeks of Bubba-ism. Not crazy about filing on the front sight either. Having a gunsmith unscrew the barrel a little does not thrill me that much either.
Therefore, have I overlooked anything that would shift the point of impact to the right while maintaining the original status of the gun? I am racking my brain and have not come up with good method. The front sight is of this type:
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Well, if you shoot the load it was designed to fire, it will likely hit POA just fine. That would be the "standard police" load of a 158 gr LRN over 4.0 gr of Unique or 3.3 gr of Bullseye, yielding about 750-800 fps. Your load of a lighter bullet at lower velocity will not match the regulated fixed sights on your Colt.

FWIW, the way the factory corrected left/right dispersion of shots was to bend the frame. I would not recommend it, though.
 
You have covered all the solutions that I know of for correcting a fixed sight revolver's POI. If none of them appeals to you then Kentucky Windage is your remaining option.
 
You have covered all the solutions that I know of for correcting a fixed sight revolver's POI. If none of them appeals to you then Kentucky Windage is your remaining option.
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I really do not like the Kentucky Windage option...no wonder I have always bought revolvers that had adjustable sights.
 
Could the barrel be canted with respect to the frame?
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It is a possibility, I will have to square the gun up and check the front sight with a machinists square or something.
I once had a three-screw Ruger Super Black-hawk that had the front sight silver soldered on at an obvious angle. I had to adjust the rear sight pretty far over to compensate for it. Using a six-inch steel ruler as a straight edge along the side of the sight, the steel rule extended the angle and it was pretty far off from vertical. With this Colt, it is hard to tell if the barrel is canted or if the sight is slightly bent...I will have to examine it further.
 
Whenever I hear the term , "Kentucky Windage" I wonder if it has bearing on the outcome of the Civil War.
 
Well, Kentucky sometimes blew with the wind.

Back to the question. I don't know of any way to install an adjustable rear sight and keep the gun in "stock condition."

I suggest first trying various loads and see if that makes a difference.

But I will, very hesitantly, mention a technique used by factories and some old time gunsmiths, bending the barrel/frame. That requires a very stiff vise, heavy bushings and a lead dead blow hammer. It is very easy to mess up and create a gap at the crane. But it can be done and solves the problem.

Jim
 
Back to the question. I don't know of any way to install an adjustable rear sight and keep the gun in "stock condition."
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Actually, I did not say that I wanted to add an adjustable rear sight. what I did say was:
I want to keep the old gun stock condition. Therefore, I am not interested in having an adjustable rear sight installed.
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Having reviewed the possible remedies, it would seem that bending the front sight slightly is the safest and least problematic of the procedures (other than to have to use Kentucky Windage). The question is then, how to proceed? A padded vise and a lead hammer? Is the front sight on old Colt Police Positives interal to the barrel, or has it been silver soldered on...I cannot tell by looking at it.
 
As stated earlier, you do not bend the sight, you bend the frame. The sight is brazed in place in a small notch. If you start hitting it with a hammer, it will break off. Then you will have two problems: how to reattach it, and how to correct windage after you get it reattached and refinished. You bend the frame. Carefully.
 
4V50 Gary:
Could the barrel be canted with respect to the frame?
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You hit it right on the head. After your post, I was looking at the front sight from the "business end", and it is apparent that the front sight was off to the left (from the front), and could be brought up into vertical alignment by screwing the barrel a few degrees.

I am relieved that there is an acceptable way of remedying the off-set sight in this old relic. Now, I need confirmation of the procedure for turning the barrel in a little more.

I have determined that a .002 feeler gage fits into the gap between the frame and the boss on the barrel. Also, the cylinder gap accepts a .006, but not .007. I do not think that the slight additional turn of the barrel will class that gap any further.

I assume that a gunsmith would clamp the barrel in a form-fitting fixture and apply rosin to keep it from turning. Then He would use a piece of wood or some other non-marring device fitted though the frame (with the cylinder removed), to turn the barrel further in, achieving sight alignment.. Generally, is that how it is done?
 
Yes the barrel will need to be clamped in a barrel vise. A piece of wood thru the fram opening "reeks of bubbaism". You should use a properly fitted frame wrench, thru the frame methods are very likely to bend the frame in which case you are SOL. GW
 
Goatwhiskers, thanks for the input. Now all I have to do is to find a gunsmith that has a Colt double-action frame wrench. Here in Michigan, we have a lot of people who call themselves "Gunsmiths"...few of which actually are.
 
Colt front sights are not brazed or silver soldered; they are just press fitted, so trying to bend the front sight risks breaking it out of the slot.

Jim
 
If you want it done inexpensively (probably just pay for postage there and back), send it to Trinidad Gunsmithing School. They have a wrench + inserts for Colts there. I know because I used the inserts for a K frame to adjust the barrel on a S&W Victory that I worked on there.
 
No shortage of skill at Trinidad. One student is machining a new safety for a C-96 Broomhandle Mauser. A classmate made a new spring for a Colt SAA. Another is repairing the hammer notches on another Colt SAA. I made a hand for a Colt Official Police and the cylinder center pin for a S&W Victory model revolver (new K frame pins have their shoulders at a different place on the centerpin). That S&W's bbl was offset at 11 o'clock and I retimed it, opened the gap and then cut the forcing cone (there was none). It's pretty common for students to make parts for older guns there.

Revolver Barrel timing is no big thing. The one thing I did was to put a drill rod into the barrel before I placed it into a lead jaw padded vise. This was to support the bbl from being crushed. I want to take the revolver class next fall. We build PPC guns in it.
 
I make a collet for the barrel vise.
I take the cylinder and yoke off the Colt.
I put duck tape on the Colt.
I use a big Crescent wrench for an action wrench.
 

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Contacted Trinidad, they stated that they could not do it until the start of the Fall semester at the earliest. Contacted Johnson's Sport Shop in Adrian Michigan, they told me they could do it, bring it in. Took it there...45 Minute drive, they examined it and told me they could and would do it. I told them I would want it done if they did not have an action wrench to fit it. They stated that if they did not have the wrench, they would bet one before working on it. I assume that they were referring to renting one if they did not have one...A Colt Police Positive is somewhat obscure these days. Well at least less common than S&W revolvers. So, it seems that I am on my way to shooting point of aim, although I just have could as try to remember to shoot for the left arm to hit the heart of a bad guy...its way to the right of the paper targets that I found imprecise.
 
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