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From a 470 with a 24" barrel, approxamately 16" sight radius, shot standing without support at 25 yards. Edit: It's a LH rifle so it went LR, LR.  Actual targets.  Composite.  The rear sight.  Reduced load fired with left and right barrel. This is the third time shooting the rifle. The first two times was in the rock quarry shooting big rocks. This was the first time firing at paper targets. After reading the thread about cheek smack, I tried holding the rifle quite a bit tighter and concentrated on rolling back at the waist during recoil. It made a big difference. Actually it would have been no problem to shoot two more full power loads but it was obvious that the rear sight needs to be moved to the left so I saved the good rounds and fired a few more reduced loads. It's getting more fun every time I shoot it. Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | ||
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Have you tried shooting it right/left, right/left? Was this rifle built as a left hand rifle from the start? Were the triggers ever reversed? Cheers Tinker _________________________________ Self appointed Colonel, DRSS | |||
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It was built as a LH rifle. Front trigger fires the L barrel. All I am asking is how far the rear sight should be moved to move the composite group to the left about three inches. Trial and error sight adjustment would be rather expensive. I was thinking about making a pencil mark on the rib at the left edge of the vertical grove on the sight and then moving the sight to the left until the right edge of that grove is lined up with the pencil mark. But that would be just a wild guess. Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | |||
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Muletrain, Just move it a skosh and see. These things are trial and error. Be sure to use the same load or it's all for naught. Jim | |||
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.020" left | |||
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Thank you, and I love your rifle. Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | |||
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Shift it slightly - 1 - 2 mm - shoot a very steady 2 or 4 shots and then see. If you are stable, you should be able to work it out with 2 shots each time so really concentrate on making sure you keep that sight picture the same. | |||
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The brownels catalog has a reference table on page 233 That shows if you have 16 " between sights you should move the sight .0133 inches. I'm not sure exactly how you will measure that. I guess with a very fine pencil line on the sight and a caliper. good luck and let us know how it goes. Just my idea after going through the process with 9 different doubles now,but if it were me I would get some snap caps and a friend. Then I would find or fabricate a good padded rest to shoot from ,standing preferably. Then I would have my friend load the gun for me with out seeing whether or not I was going to fire with a snap cap or a loaded round. Have him watch you as you shoot. If you have no flinch you should have a very good idea exactly what the rifle if doing. Then I would adjust the sights.  If you own a gun and you are not a member of the NRA and other pro 2nd amendment organizations then YOU are part of the problem. | |||
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You know your stuff, don't you...  Jack OH GOD! {Seriously, we need the help.} | |||
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Muletrain, The amount of sight movement required is based on similar triangles. One for your sight radius and one for your target impacts at a given distance. Butch gave you the answer on how much and what direction to move your rear sight, 0.020". I'll assume that you don't have a depth micrometer or a vernier depth (Watervliet) gauge. 0.015" = 1/64" so you want to move it just a bit more than that. Many reloaders have vernier calipers, the old style or dial. The newer digital ones might not work with my method. I've never used digital mics or verniers. To measure the 0.020", use the rod on a vernier caliper. This rod is flush with the right side end of the caliper when zeroed. If you measure 0.020, or whatever amount on the vernier, the rod will stick out that much. It works pretty well. Measure the depth between the side of your rear sight and the rib. Loosen your sight lockscrew and move the sight 0.020" to the left as Butch said, re-tighten the screw and check your measurement. If you are facing your sight as in the photo, the measurement should increase if you measure on the left side of the sight or it should decrease if you measure from the right side. Hope this helps you. You have a nice shooter there. Use a double rifle. It just feels better. Double Rifle Shooters Society | |||
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Thank you. I do have a dial caliper with a depth rod. That sounds like the perfect way to do it. Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | |||
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Case closed! ....Mac >>>===(x)===> MacD37, ...and DUGABOY1 DRSS Charter member "If I die today, I've had a life well spent, for I've been to see the Elephant, and smelled the smoke of Africa!"~ME 1982 Hands of Old Elmer Keith  | |||
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Looks like you're on the right track! For future reference, the formula (which I've found to work perfectly) from the Brownell's gang is as follows: To Determine Sight Adjustment: Use the following equation to determine the change you need to make: Sight change = Sight Radius (multiplied by) Impact distance (that quantity, dividied by) Target distance Sight Radius: Distance between front and rear sight Impact distance: Measurement from point of aim to bullet impact Target distance: Measurement from muzzle to target Sight change: Amount of correction needed Sight rule: Move rear sight in the direction you want the bullet to move. Move front sight the opposite direction you want the bullet to move. Hope that helps! Cheers Tinker _________________________________ Self appointed Colonel, DRSS | |||
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16" sight radius x 3" impact distance / 900" target distance = .053 Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | |||
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Muletrain is correct, it is .053. The target distance is 25yds. If the target distance was 50yds it would be .02. It must be remembered for those not familiar with the sight change formula that all measurements are in inches, so a 25yd target is 25x36in for 900 divisor. Von Gruff. | |||
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We shall see. I moved it .02 as Mr. Searcy stated. .05 just looks like it would be too far. Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | |||
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Yep I goofed the table on page 233 is for 100 yrds. Let us know how it turns out If you own a gun and you are not a member of the NRA and other pro 2nd amendment organizations then YOU are part of the problem. | |||
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Dosen't look like he has .020 room to move the sight. The only easy day is yesterday! | |||
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How did you work that out ? There is plenty of room to move the sight .02". | |||
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I believe that you will find that Muletrain is correct. Your sight distance is 16" and your target distance is 900" and you need to move your POI by 3". So: 900"/3"=300 (3" POI change@25 yards) 16"/x"=300 (x will be your required sight movement) You could also look at this as: 900"/3"=16"/x" - So: 900=48/x - So: 900x=48 - So: x=48/900 - So: x=.0533333" x=0.05333333333333333333333333333333" Moving your rear sight .020" will only change POI by 1.125" Jason "You're not hard-core, unless you live hard-core." _______________________ Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt. Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure. -Jason Brown | |||
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I agree. It looks like the sight is nestled between the barrels with no room for windage adjustments. Is the front sight moveable? If so, move it in the opposite direction you want the bullet to go. Jim | |||
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Good point. I always seem to convert sight adjustments at the end to mm's as I find it easier to measure smaller movements in mm's on sights than trying to work out .020 of an inch. Hence why I said 1 - 2mm. | |||
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There is actually quite a bit of room to move it either way. Elephant Hunter, Double Rifle Shooter Society, NRA Lifetime Member, Ten Safaris, in RSA, Namibia, Zimbabwe | |||
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FWIW, I needed to move my .303 double's POI three inches left at 100 yards. Moved the back sight about 1mm (.04 in) left and the next set of four were fine. Believe the "move it a skosh and try" is the way forward here. Best for the New Year, Tim | |||
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That sight is completely removable. He could drift it all the way off the rib if he wanted to.
_________________________________ Self appointed Colonel, DRSS | |||
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I put my money on Butch Bill Member DSC,DRSS,NRA,TSRA A man who carries a cat by the tail learns something he can learn in no other way. -Mark Twain There ought to be one day - just one – when there is open season on Congressmen. ~Will Rogers~ | |||
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So did Muletrain! 
If I were in his shoes that'd be the first move I'd make too. Got a sense Butch has done this a time or two in the past. As effective as that formula has been for me in the past, most of the application has been on single-barreled rifles. We'll see how much hoo-doo there's in the sights of that double rifle soon! Cheers Tinker _________________________________ Self appointed Colonel, DRSS | |||
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Yeah, 0.0533, assuming I could shoot well enough to see that difference! ------------------------------- Will Stewart / Once you've been amongst them, there is no such thing as too much gun. --------------------------------------- and, God Bless John Wayne. NRA Benefactor Member, GOA, N.A.G.R. _________________________ "Elephant and Elephant Guns" $99 shipped “Hunting Africa's Dangerous Game" $20 shipped. red.dirt.elephant@gmail.com _________________________ Hoping to wind up where elephant hunters go. | |||
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That's just about 1/16"...
...about the width of a front sight blade or bead. If you can see the front sight, you can make that much of a (sighting mistake or...) difference in the placement of your aggregate group. Cheers Tinker _________________________________ Self appointed Colonel, DRSS | |||
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Interesting point. You gave me an idea(which usually means trouble). Why not make 2 marks just below the top edge of the rear sight with a pencil or white-out, one .020" over from center, and the other .053" from center. You can use these to check the amount of movement that will be needed without adjusting anything. Jason "You're not hard-core, unless you live hard-core." _______________________ Hunting in Africa is an adventure. The number of variables involved preclude the possibility of a perfect hunt. Some problems will arise. How you decide to handle them will determine how much you enjoy your hunt. Just tell yourself, "it's all part of the adventure." Remember, if Robert Ruark had gotten upset every time problems with Harry Selby's flat bed truck delayed the safari, Horn of the Hunter would have read like an indictment of Selby. But Ruark rolled with the punches, poured some gin, and enjoyed the adventure. -Jason Brown | |||
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