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Every hardware store I know of will have key stock in plain and plated, inch and metric. "Woodruff" keys are a semi-circle, plain keys are square or rectangular. They're generally mild steel and all you need.
 

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Raise front sight to lower POI

Your post said barrel is 7.5", and POI is 6 to 7" high. First, confirm exact measurement between front and rear sight.If it is 7.5", and you want to lower POI by 6" at 25 yards then equation is:

25 yd x 3 ft/yd x 12"/ft = 900"

Increase in height of front sight =y

y= 7.5" x 6"/900"= 0.05"

I assume you can't lower rear sight. The amount to lower would be the same, i.e. 0.05".Or you can lower rear by 0.025" and raise front by 0.025".
 

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I would find a thin piece of plastic, paint it black and super glue it onto the front blade. I'd make sure it was about 2 x as thick as you originally calculated so you could have some movement on the back site.

but that's just me.
 

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Guys,

My 7 & 1/2" .44 Super Blackhawk shoots everything high - about 5-6" at 25 yds. with slower 240 and 250 gr. lead, 4" or so with the lighter/faster jacketed 200 & 210"s at near max. Even gripping it pretty firmly. Even with rear sight all the way down.

So I can either remember to hold low on everything, or I need to somehow add 1/16" or so to the front sight. The proper way I suppose would be to silver solder a piece of steel on top, but if I can come up with something easier, I'd prefer it. I wish somebody made some square fiber-optic pieces that I could JB weld on top.

I'm thinking of JB welding a thickness or two of credit card just to verify the height I need to add.

I could use a smart idea … or somebody help me avoid making a terrible mistake....
Others seem to have provided enough suggestions on modifying the sights, but I'll comment on the difference of impact points of heavy versus lighter bullets. I have been told that, in a pistol, heavier bullets tend to shoot higher since they move slower and have more "barrel time" giving the muzzle more time to rise from the recoil before the bullet exits the end of the barrel. Thus, you may want to standardize on what bullet weight to shoot, otherwise you need to come up with sight modifications necessary to compensate for the highest rising bullet so that you can then adjust the rear sight up when shooting lighter bullets that don't shoot as high.
 

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Discussion Starter #25
All good suggestions. The actual sight radius on this gun with a 7.5" barrel is closer to 10.5", as JBelk said. Yes, lighter/faster bullets print lower, and slower/heavier bullets print higher. I suspect this is exaggerated in a single action gun due to the grip design and the bore axis being higher in relation to the grip than on some double actions - it seems that recoil tends to rotate the gun in the hand a little more, whereas in my double actions a little more is directed back into the hand. At any rate, the spread isn't as noticeable with my Redhawk and Model 29's as it is in the SBH.

I will raise the front sight a bit more than needed, so I can use more of the range of the rear sight to compensate for various loads in the future. It's screwed all the way down now. I could file it off a little and deepen the notch, but not much, and it would still be screwed all the way down.

I plan to get some 1/8" key stock this weekend. I thought about plastic, just to test, but I'd rather do it once and do it right.
 

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I acquired a second hand Army San Marco replica 1871 Richards conversion revolver. I soon found it shot 6" high at 25 yards even though the previous owner had cut down the rear sight till there was virtually nothing left. To get it zeroed and have a useable sight picture I had to make new blades both front and rear. If the previous owner had made some measurements and done some simple common sense math he'd have know he could never get the needed correction by cutting away the rear blade. That would have saved me a lot of aggravation since making and fitting the rear blade was a lot more challenging than simply making a new front blade. Of course, if he had fixed it properly maybe he'd not have wanted to sell it, it is a tack driver.
 

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I keep hearing 'cut the rear notch deeper'. That does no good. The top of the rear sight has to be cut down to affect aiming. The notch is cut deeper to keep the same sight picture. Talking about pistol/revolver square notches and matching fronts here. African vees and beads are different.

In the '80s it was common to rebore or rebarrel old crusty Hollands and Rigbys and Westleys that had done hard times in India and Africa. Some had multi-leaf express sights that were now way off. The sight correction formula is used to do the rough estimation after the first shot gives the base line. It saves ammo and tremendous wear and tear on the body to be able to zero a rip snorter in three shots and confirm in two. Wide African vee sights are very unforgiving of mistakes and expensive to replace so the math is valuable and proven many times to be accurate.
 

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Elk Whisperer (Super Moderator)
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I could file it off a little and deepen the notch, but not much, and it would still be screwed all the way down.
I wouldn't. I made that mistake on my Old Army and it gained me nothing, zero, zip, nadda, except the need to purchase a new piece.

I plan to get some 1/8" key stock this weekend. I thought about plastic, just to test, but I'd rather do it once and do it right.
YES, exactly, there is a good bit of adjustment in that rear sight assembly, about 3/32" .

Even if you hafta file a piece of key stock "narrower" first, but if memory serves, the sight blade is 1/8" ?

In my SBH Hunter I only use one weight of bullet, 255 grain cast and leave the hot jacketed loads for the Redhawk. :D

RJ
 

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I suspect this is exaggerated in a single action gun due to the grip design and the bore axis being higher in relation to the grip than on some double actions - it seems that recoil tends to rotate the gun in the hand a little more, whereas in my double actions a little more is directed back into the hand. At any rate, the spread isn't as noticeable with my Redhawk and Model 29's as it is in the SBH.
The grip is at least part of the issue, as my 5.5" SBH is bullet weight limited to 265gr-270gr jacketed bullets to have a usable hold on a 6" bull at 25yds. 300gr bullets shoot higher by about 18" with the rear sight bottomed out. My M69 is just about the same, or more like exactly the same. I need to float a 6" bull with a 6 o'clock hold just at the top of the sight blade with the rear sight bottomed out. Not a big issue, but it tells me weight and barrel length are also an effect. My 10" SBH, no problem, but it's not exactly portable. Great for rams at 200M, would be outstanding for hunting with a handgun, but just hanging on a belt, not so much.

What I've often wondered is if it might be worth milling the existing sight off the 5.5" SBH, and machining a slot with a pin for a different blade heights. ??
 

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Just install an adjustable front sight. Ross Seyfried did that on his first .475 Linebaugh. With front and rear adjustable, everything works.
 

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The Hog Whisperer (Administrator)
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When I was working up loads for the .500 JRH (single action BFR), the difference in point of impact at around 20 yards was astounding, from the lightest/fastest to the slowest/heaviest. Will have to try and find the picture. Something like a foot, or maybe foot and a half. Those 500gr. bullets at 1,200fps really get your attention! :eek:

Slinging Hornady 300gr. FTXs at 1,500+ fps was much easier on the hands, but the muzzle blast would clear the shooting bench. Ever blown a full box of cartridges off the bench? :D
 

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Discussion Starter #32
I got the 1/8" key stock yesterday, cut a piece off to fit, filed the top of the existing sight flat, filed the zinc plating off the key stock, and JB welded it in place. After it set, I rounded the front and back edges slightly. The cold blue darkened it some. Off to the range this afternoon, I think. May have to file the front down some, we'll see. It would be nice to come out using about half of the usable clicks in the rear sight, so I can adjust between slower LSWC's and faster jacketed loads.
 

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Just install an adjustable front sight. Ross Seyfried did that on his first .475 Linebaugh. With front and rear adjustable, everything works.
Remove the existing sight, or mill a dovetail?

I can see the SS SBH's have a pinned front sight, on what appears to be a similar base like my 80's 5.5" SBH. The SBH Hunter's have a dovetailed slot, that would be fine if there are aftermarket options. Not sure how the existing front sight on my SBH is attached, (silver soldered?), but it's actually on straight and I'd hate to mess it up. Or, I suppose I could just leave it as is and use my supply of Hornady 265gr FP's. The economy route.
 

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Tman--- I said that rather flippantly. The job is not easy. It involves milling off the blade and milling a slot on the top of the ramp. the new blade is pivoted in the center with a spring on one end and an adjustment screw on the other. The factory ramp limits the amount of movement due to its short height. The job is usually a custom part made for the gun at the time of building it.
Ross did it because it was a test gun for many different loads.

Sorry for the picture quality. It was taken through the glass of the framed picture. This is the adjustable front put on Ross' 5" .475 Linebaugh with two leaf express rear.
 

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Elk Whisperer (Super Moderator)
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I got the 1/8" key stock yesterday, cut a piece off to fit, filed the top of the existing sight flat, filed the zinc plating off the key stock, and JB welded it in place. After it set, I rounded the front and back edges slightly. The cold blue darkened it some. Off to the range this afternoon, I think. May have to file the front down some, we'll see. It would be nice to come out using about half of the usable clicks in the rear sight, so I can adjust between slower LSWC's and faster jacketed loads.
Good luck!

One can "blacken" the added.piece with flat black nail polish too. :D

RJ
 

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Elk Whisperer (Super Moderator)
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Just the sides, then I put flat white on the top of the blade.

My preferred color for spring is bright green with black and red dots but I can't go to my nail gal with the social distancing and all. Woe is me

RJ
 
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Discussion Starter #39
At the range yesterday, the 1/8" sight addition lowered the groups about 8-10", (at 25 yds) , about 4" too much, so I ended up with the rear sight maybe 2/3 of the way up. That puts the 240 and 250 LSWC's at 44 spl velocities to about POA, and hotter jacketed stuff about 3" low.

The last 2 shots of about the 5th 6-shot group were off the paper. (I found the sight addition on the bench). Back home, I roughed up both surfaces hoping that helps the JB weld bond better, then filed the addition down some more. Maybe it being lighter will help, too (?)

If this doesn't hold, not sure what to do. I have some silver solder, but only a regular torch, and almost no experience.
 

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What type of JB Weld did the OP use? There are many types sold, but the original is best...the Kwik set doesn’t hold as well, neither does the putty. The surfaces need to be very clean, and roughing them up a bit does help. Minimum 24 hours to fully harden.

Properly done there is no way JB won’t hold a tint piece of metal during recoil. It should be able to withstand a good tap with a hammer....

https://www.jbweld.com/product/j-b-weld-twin-tube



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